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Ugh. You know one of the last act of the military if Japan were going to take over Hawaii is to destroy everything of military value. Drydock, fuel storage, military supplies, and basically everything of military use.

 Jihadin wrote:
Ugh. You know one of the last act of the military if Japan were going
to take over Hawaii is to destroy everything of military value. Drydock, fuel storage, military supplies, and basically everything of military use.

Then capture them...seize Hawaii, suppress the West Coast's shipyards, and close the Panama Canal.

 Tadashi wrote:

 purplefood wrote:
Submarine carriers?
The ones that could only carry 3 aircraft at a time?

What makes you think Japan wouldn't have improved the design (either of the submarine-carriers or the planes or the weapons) for a sustained effort to keep the Panama Canal closed.

Well it's not exactly a feasible technology at the time... I don't know if it's feasible now to be honest.
It'd also be a huge drain on resources.
You have to keep loads of submarines there at massive cost in fuel and probably munitions, not to mention casualties.
Whereas the US Navy just has to build loads of destroyers to sink the submarines. Which it could do...

 purplefood wrote:

 Tadashi wrote:

 purplefood wrote:
Submarine carriers?
The ones that could only carry 3 aircraft at a time?

What makes you think Japan wouldn't have improved the design (either of the submarine-carriers or the planes or the weapons) for a sustained effort to keep the Panama Canal closed.

Well it's not exactly a feasible technology at the time... I don't know if it's feasible now to be honest.
It'd also be a huge drain on resources.
You have to keep loads of submarines there at massive cost in fuel and probably munitions, not to mention casualties.
Whereas the US Navy just has to build loads of destroyers to sink the submarines. Which it could do...

Depends on how you use the submarine-carriers: if you avoid combat and concentrate on keeping the Gatun Locks destroyed and the Canal's integrity, you wouldn't all that many of them...not to mention the nightmare of sending ships through the Straits of Magellan in military terms, and with the West Coast's shipyards under interdiction.

 Khornholio wrote:
If the Japanese had gone with the Army's plan to invade Siberia to get oil and materials rather than the Navy's plan to go south and take the oil from South East Asia, I believe the war would've had a different outcome as the United States' entry would've been prolonged, if they entered at all, and the Soviets would've been fighting on two fronts. As with any point-counter point made in alternative history talk, it's all speculation.

This is completely wrong. The military faction arguing for the push into Siberia was originally dominant... and managed to provoke border skirmishes into outright war at Khalkhin Gol. Except the Japanese got absolutely smashed, as while they had a tactically skilled, disciplined army, it was massively behind even the Russians on basic logistical capabilities. When the Soviets armoured pincers engulfed the Japanese and inflicted a devestating defeat the Japanese learned there was no way they could push North.

In fact, the stomping at Khalkhin Gol was so emphatic that the Japanese didn't dare do anything even when the Soviets were obviously supplying the KMT with equipment and training to fight the Japanese. It was such a beating that even when their ally Germany went to war with the Soviets there was little real argument in Japan to attempt to push North. Even as the Germans smashed the Soviets in the early months of the war, Japan didn't dare push North. Because as impressive as the Japanese navy was, their army was still second rate, and could not match an industrial power in open war.

A better hypothetical here would be 'what if the Japanese hadn't been insanely cruel in China?' There was little real support for the warlords of the KMT, and the communists were not at that stage a functioning alternative, so what if Japan had managed to win over the Chinese population. Instead of seeing so many men and resources squandered in China, could a more successful invasion have they instead have gained men and resources, and maybe been in a better position to consolidate their holding in Asia?

As for the Nazis not existing, the outcome of World War I, including the Treaty of Versailles, and the rise of fascism in Italy would also have to be vastly different. IF the entente had lost World War I, who is to say there wouldn't have been French fascism and British National Socialism?

You can speculate a Nazi free Germany without having to go back to Versailles or the outcome of WWII. You could just propose that the Socialists win instead. Or that neither extremist faction takes hold, and eventual economic recovery sees a return to moderate politics.

But I do agree that if the result of WWI had been different and it was the entente that lost, then Nazism was at least as likely to rise in either France or Britain. Even without that, Nazism was at least as likely to rise in France.


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 LordofHats wrote:
Japan's only shots at winning in the Pacific were to follow up the damage done at Pearl Harbor with a decisive naval engagement (which they attempted at Midway and Coral Sea), but the Japanese Navy just couldn't bring this kind of engagement to conclude in their favor. Midway was a disaster for the IJN, all over a piece of land that was strategically useless to Japan. Coral Sea was the consequence of a Navy that continued to hold to the theory of the big gun ship when faced with a Navy that had few battleships but a good number of carriers.

Even if the Japanese had achieved their second decisive engagement (say, for instance, that the good luck enjoyed by the US at Midway went the other way), then the Japanese were really hoping that the US would put their tails between their legs and agree to grant the Japanese open season in the South Pacific. Because they certainly couldn't have even pretended at an invasion of mainland USA, so their only hope was that the Americans would just give up and sign a treaty.

And I think we all know that was never going to happen.

Destroying battleship row inadvertently helped the US win the Pacific war. Carriers at the time were cheaper and faster to produce, so we built them and it turns out that at the time the naval strategy of swarming a big gun fleet with planes just worked out marvelously.

That's not quite right. The US continued to build battleships through the war. And both sides continued to treat their battleships as key elements of their fleets, and remain wary of the threat of the major capital ships of the other side. It was only really in the aftermath of the war that the aircraft carrier was really acknowledged as the primary element of naval power.

 Tadashi wrote:

 Jihadin wrote:
Ugh. You know one of the last act of the military if Japan were going
to take over Hawaii is to destroy everything of military value. Drydock, fuel storage, military supplies, and basically everything of military use.

Then capture them...seize Hawaii, suppress the West Coast's shipyards, and close the Panama Canal.

"We would blow them up if they were going to capture them"

"then capture them"

Watched an interesting Alt History film the other day..
"CSA; The Confederate States of America".
Basics, The Confederacy wins the Civil war then overruns the North. Canada becomes an enemy state, and the new government invades Central and South America. The country never enters the war in Europe as the government sees Hitler as an ally.
Interesting points come at the end of the film: The Confederacy basically needed ONE decisive victory to pull in support from England and France, and that is what makes the difference.

 Tadashi wrote:

 purplefood wrote:

 Tadashi wrote:

 purplefood wrote:
Submarine carriers?
The ones that could only carry 3 aircraft at a time?

What makes you think Japan wouldn't have improved the design (either of the submarine-carriers or the planes or the weapons) for a sustained effort to keep the Panama Canal closed.

Well it's not exactly a feasible technology at the time... I don't know if it's feasible now to be honest.
It'd also be a huge drain on resources.
You have to keep loads of submarines there at massive cost in fuel and probably munitions, not to mention casualties.
Whereas the US Navy just has to build loads of destroyers to sink the submarines. Which it could do...

Depends on how you use the submarine-carriers: if you avoid combat and concentrate on keeping the Gatun Locks destroyed andthe Canal's integrity, you wouldn't all that many of them...especially seeing as it would be a nightmare just sending ships through the Straits of Magellan in military terms, and with the West Coast's shipyards under interdiction.

Under interdiction from what?
More submarine carriers?
Just build more destroyers...
At the height of Germany's blockade on Britain the US was able to build more ships than the German U-boats could sink and they were really good at their job.
The Japanese submarine carriers reported fairly limited success as submarines let a lone carriers...
The US has the production capacity to out-build Japan.

Submarine carriers may be viable now, but only because of drone technology.

A Submarine can carry loads more drones then it can carry full sized aircraft.


Lets envision a submarine carrier that can carry some VTOL aircraft, cause thats the only sort of jet aircraft that will be able to take off and land on a Submarine.

The submarine is going to have to be HUGE to carry more then 4 of these things. You have to carry large amounts of fuel, lodging for the pilots, maintainance hangers, replacement parts, etc...

The sub will also have very little room for any secondary armament systems like Torpedos or Missiles. its sacrificing alot of firepower for less then half a dozen planes.

A huge sub that can carry a half dozen planes is going to be massive, its going to be hard to hide something like that. Even in the ocean. For a ship thats main advantage is surprise its not very good at hiding. Not to mention that its going to be an easy target once it is spotted.





Drones could make Subcarriers viable nowdays, but in the WW2 era they were nothing but a pipedream.

 Grey Templar wrote:
Submarine carriers may be viable now, but only because of drone technology.

A Submarine can carry loads more drones then it can carry full sized aircraft.


Lets envision a submarine carrier that can carry some VTOL aircraft, cause thats the only sort of jet aircraft that will be able to take off and land on a Submarine.

The submarine is going to have to be HUGE to carry more then 4 of these things. You have to carry large amounts of fuel, lodging for the pilots, maintainance hangers, replacement parts, etc...

The sub will also have very little room for any secondary armament systems like Torpedos or Missiles. its sacrificing alot of firepower for less then half a dozen planes.

A huge sub that can carry a half dozen planes is going to be massive, its going to be hard to hide something like that. Even in the ocean. For a ship thats main advantage is surprise its not very good at hiding. Not to mention that its going to be an easy target once it is spotted.


Drones could make Subcarriers viable nowdays, but in the WW2 era they were nothing but a pipedream.

I didn't think of drones...

Glorioski wrote:
Good for you.

I probably would take more interest if any of the other, many, questions raised by the OP's hypothetical situation were explored other than the boring 'How could America possible be beaten by Japan' one.

It's always seemed strange to me, given the immense amount luck enjoyed by the Axis powers in the early stages of WW2, that we get so little speculation on any of that going wrong.

Like, what if the Mechelen incident had never happened, and the Nazis had tried to drive through the low countries. Their officer corps was sorely lacking in training (having expanded from 100,000 to 5.5million troops in just a couple of years). They had very few MkIII or MkIV tanks, and only enough bombs for 14 days of operation for their planes. And they were marching straight into the plan the British and French were prepared for. Disaster was almost inevitable. So what then? Do the Soviets see the German state collapsing as an opportunity to advance West (or do they see the Winter War as enough of a warning that they are not ready?) Is Germany dismantled, or are they given another chance at liberal democracy?

 purplefood wrote:

Under interdiction from what?
More submarine carriers?

Hawaii-based Aircraft Carriers. Equipped with reverse-engineered technologies obtained from the Pearl Harbor Naval Yards...

 Grey Templar wrote:
Wait what?

Whats the Titanic have to do with WW1?

Or is my sarcastic meter broken?

Well, Charles Lightoller was the most senior officer to survive the Titanic disaster, and later skippered his private yacht to help in the evacuation of British and French troops from Dunkirk. But other than that Titanic doesn't really have much to do with any war, near as I can figure.

 purplefood wrote:

 Grey Templar wrote:
Submarine carriers may be viable now, but only because of drone technology.

A Submarine can carry loads more drones then it can carry full sized aircraft.


Lets envision a submarine carrier that can carry some VTOL aircraft, cause thats the only sort of jet aircraft that will be able to take off and land on a Submarine.

The submarine is going to have to be HUGE to carry more then 4 of these things. You have to carry large amounts of fuel, lodging for the pilots, maintainance hangers, replacement parts, etc...

The sub will also have very little room for any secondary armament systems like Torpedos or Missiles. its sacrificing alot of firepower for less then half a dozen planes.

A huge sub that can carry a half dozen planes is going to be massive, its going to be hard to hide something like that. Even in the ocean. For a ship thats main advantage is surprise its not very good at hiding. Not to mention that its going to be an easy target once it is spotted.


Drones could make Subcarriers viable nowdays, but in the WW2 era they were nothing but a pipedream.

I didn't think of drones...

Yeah, a Submarine Carrier could probably have at least a dozen, if not more, Drones. Possably a firepower comperable to a conventional carrier.


And the nice thing is, the Sub can move undetected, launch its drones, and then the Drones could wait in the airspace for weeks at a time while the Sub returns to a safe distance. Then the Drones can strike the targets, get picked back up and rearmed, and be back in the airspace within a few hours.

The Drones also eliminate the need for crew accomodations on the Sub. They only need crewmen to service and rearm the drones. Cutting back on the space needed in the sub.

 Grey Templar wrote:
If we had invaded, the entire Island would likely have been annhilated. The entire populace was ready to fight, down to the last women and child.

That's a matter for debate. It was certainly believed to be true at the time, but then back then we didn't have much of a problem putting alien mindsets onto Asian people.

It probably would have ended up a really bloody, ugly invasion with loads of casualties on both sides, more or less like the Russian capture of Berlin. But most civilians would have probably fled the fighting, and looked first to protect their families, same as everywhere else in the world.


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 Jihadin wrote:
Ugh. You know one of the last act of the military if Japan were going to take over Hawaii is to destroy everything of military value. Drydock, fuel storage, military supplies, and basically everything of military use.

Maybe. Panic sets in, especially when people aren't pschologically ready for the invasion, or properly trained in the event it does. There's no shortage of stories of bridges, water supplies and munitions being captured when it simply should not have happened.

I think it's unlikely the Japanese could have captured meaningful levels of supplies from Pearl Harbour, but you can't just decide it never would have happened.

 Tadashi wrote:

 purplefood wrote:

Under interdiction from what?
More submarine carriers?

Hawaii-based Aircraft Carriers. Equipped with reverse-engineered technologies obtained from the Pearl Harbor Naval Yards...

Implying you have captured both the US technology and reserves of fuel...
I don't know about you but the first thing I would do if the enemy was going to capture massive reserves of fuel and some advanced technology is blow it all to hell...
Lets face it. Capturing the fuel reserves is not a certain thing, the technology? Maybe but even then it's not a certain thing.

I'm not sure whether or not it would be feasible for Japanese carriers to interdict American Dockyards...

 Tadashi wrote:
What makes you think Japan wouldn't have improved the design (either of the submarine-carriers or the planes or the weapons) for a sustained effort to keep the Panama Canal closed?

As I already pointed out to you, that kind of sustained strategic operation was not in the thinking of Japanese officers at the time. Look at the incredible damage inflicted by US submarines on Japanese shipping into China. While their merchant fleet was being absolutely trashed the Japanese continued to give token escorts at best, all the while they kept their main fleet together trying to score a decisive engagement against the Americans.

Now you can speculate 'what if the Japanese had developed a long term understanding of the importance of industry in modern war?' Well then they probably would have developed an understanding of the importance of industry and economic growth in general, and focused on continuing reform of Japan's economy, and not gotten themselves involved in a stupid, pointless war.


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 purplefood wrote:
Implying you have captured both the US technology and reserves of fuel...
I don't know about you but the first thing I would do if the enemy was going to capture massive reserves of fuel and some advanced technology is blow it all to hell...
Lets face it. Capturing the fuel reserves is not a certain thing, the technology? Maybe but even then it's not a certain thing.

I'm not sure whether or not it would be feasible for Japanese carriers to interdict American Dockyards...

It's plausible that they captured both, but by no means likely, and certainly no guaranteed.

But if they captured US radar would they have even recognised the value of it? The US regarded it as little more than a toy at the time, despite its successful use by the British in the Battle of Britain. Iit was only in the wake of Pearl Harbour that they realised what might have been averted if they'd taken radar more seriously that they changed. Would the Japanese have seen the radar facility and thought 'here is a technology for telling you where the enemy planes are that we just captured from an enemy who had no idea where our planes were, so it clearly works great and we better spend our limited resources building as much of it as possible.'

 purplefood wrote:

Under interdiction from what?
More submarine carriers?
Just build more destroyers...
At the height of Germany's blockade on Britain the US was able to build more ships than the German U-boats could sink and they were really good at their job.
The Japanese submarine carriers reported fairly limited success as submarines let a lone carriers...
The US has the production capacity to out-build Japan.

No, most likely the surface fleet would have to do the interdicting along the US west coast. It's hard to build ships if your slip ways are covered in bomb and shell craters, and there are a limited number of possible targets. Sen toku class boats were something of a Pie in the Sky idea that might have actually worked. In reality, without a viable US surface fleet, it would have been easier to deploy a squadron of light cruisers and maybe some Kongo class BBs, and shell it back to the stone age.

 Jihadin wrote:
Ugh. You know one of the last act of the military if Japan were going to take over Hawaii is to destroy everything of military value. Drydock, fuel storage, military supplies, and basically everything of military use.

In a Japanese invasion scenario, using the 14th Army:

To win the Japanese effectively would have to advance two miles inland. They have surprise, overwhelming air superiority, elite units trained specifically for amphibious ops, close fire support way beyond anything the US could hope to have with the battleships sunk, and outnumber the defenders 3 to 1. On top of that, the US Navy and Army spent a lot of time and money making the facilities very difficult to damage to fend off the possibility of sabotage by the large number of ethnic Japanese living in Hawaii. Hell, the fuel tanks at Red Hill were designed to withstand direct battleship fire without damage. The old Army Command center there, not so much.

I hate to say it, but the defenders around Pearl itself would have been over run faster then you can say 両手をあげろ！

There would be a better defense around Honolulu, and they might have been able to damage the civilian port facilities before being over run.

Remember, that Pearl's defenses very much revolved around the Navy and air power. Frankly, once an invader had boots on the ground, it was game over.

 Galdos wrote:

So in other words, the US had superior technology in the transportation field allowing it to transport its MBT the M4 Sherman to battle zones while Japan is unable too. That actually supports what I just said thank you.

If by superior technology you mean 'scads more of them' sure. If by 'superior technology' you mean a direct ship to ship comparison... no. Further, the Sherman is not an MBT. THe MBT designation for tanks came about long after the Sherman left US service. The M4 was classified as a medium tank, which at the time meant that it was a direct fire support tank for the army. It's astonishingly lackluster ability when faced with contemporary tanks in it's own weight class led to thier nickname. Ronsons.

 Galdos wrote:

And Ships, all the Allied ships were superior to their Axis counterparts, from the Fletcher class Destroyer to the Iowa class Battleships, to the American Carriers which after Midway, were being built with metal flight decks, not wood, something Japan continued with to the end of the war.

Well, point of fact, Japan built very few carriers at all between the beginning and end of the war, however the Taiho class had armored decks. Of the US carriers, only Yorktown, Essex and Midway class boats had armored decks.

While the Iowa class battleship was, in many ways, superior to most battleships, Iowa vs Bismark/Yamato class again is much more in doubt. If Japan or Germany had the industrial capability to produce the so called superbattleships and carriers in the sort of quantities that the US did, the US would have quickly lost the war.



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 sebster wrote:

But if they captured US radar would they have even recognised the value of it? The US regarded it as little more than a toy at the time, despite its successful use by the British in the Battle of Britain. Iit was only in the wake of Pearl Harbour that they realised what might have been averted if they'd taken radar more seriously that they changed. Would the Japanese have seen the radar facility and thought 'here is a technology for telling you where the enemy planes are that we just captured from an enemy who had no idea where our planes were, so it clearly works great and we better spend our limited resources building as much of it as possible.'

Yamamoto would have had them working day and night on it, as it was a technology that would compliment his idea of how carriers and battleships worked together.


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 Grey Templar wrote:


Drones could make Subcarriers viable nowdays, but in the WW2 era they were nothing but a pipedream.

Well, IIRC they built four of that pipe dream, and the US was so desperate to keep them out of Russian hands they scuttled them after capturing them. However, they were more or less designed for a single mission, the destruction of hte Panama Canal.


What's really viable again is airships. Consider a drone carrier capable of over one hundred thousand tons of lift. Now cover it in modern CIWS on a rigid airframe with variable prop engines.

 BaronIveagh wrote:

 sebster wrote:

But if they captured US radar would they have even recognised the value of it? The US regarded it as little more than a toy at the time, despite its successful use by the British in the Battle of Britain. Iit was only in the wake of Pearl Harbour that they realised what might have been averted if they'd taken radar more seriously that they changed. Would the Japanese have seen the radar facility and thought 'here is a technology for telling you where the enemy planes are that we just captured from an enemy who had no idea where our planes were, so it clearly works great and we better spend our limited resources building as much of it as possible.'

Yamamoto would have had them working day and night on it, as it was a technology that would compliment his idea of how carriers and battleships worked together.

My thoughts exactly.

However, they were more or less designed for a single mission, the destruction of hte Panama Canal.

That aspect of them would not change.


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 sebster wrote:


Now you can speculate 'what if the Japanese had developed a long term understanding of the importance of industry in modern war?' Well then they probably would have developed an understanding of the importance of industry and economic growth in general, and focused on continuing reform of Japan's economy, and not gotten themselves involved in a stupid, pointless war.

Now you can speculate 'what if the Americans had developed a complete understanding of the cultural differences in the world?' Well then they probably would have developed an understanding of the importance of 'leaving well enough alone', and focused on continuing reform of America's economy, and not gotten themselves involved in a stupid, pointless war in the Middle East.

 BaronIveagh wrote:
No, most likely the surface fleet would have to do the interdicting along the US west coast. It's hard to build ships if your slip ways are covered in bomb and shell craters, and there are a limited number of possible targets. Sen toku class boats were something of a Pie in the Sky idea that might have actually worked. In reality, without a viable US surface fleet, it would have been easier to deploy a squadron of light cruisers and maybe some Kongo class BBs, and shell it back to the stone age.

Seriously? Direct naval action against major port facilities?

You do know how terrible an idea the allies thought that was, even with the combined might of the Atlantic fleet. And you are aware that planes can take off from land, and make any idea of sitting a boat off the West coast of the USA look incredibly stupid very quickly.

Yamamoto would have had them working day and night on it, as it was a technology that would compliment his idea of how carriers and battleships worked together.

You make that sound as if Yamamoto would have been magically, instantly aware of the capabilities of the technology, which is a massive stretch given the reason I already stated - people do not see the power of a technology that the only captured because the enemy failed to use that technology at all.

Oddly, men Like MacArthur and Nimitz were not entirely certain of Victory. I think they were better judges of it than anyoen in this thread.

MacArthur and Nimitz didn't have the advantage of hindsight.

Tadashi wrote:1) Capturing the oil depots at Hawaii would have given the fleet enough resources to maintain an extended North Pacific campaign, and the SE Asian oil fields would just be a bonus.

I guess no one at all here realizes the logistical horror of operate a fleet across 3000 miles of ocean to Hawaii while simultaneously engaged in the south pacific and Indian ocean. It would take all the oil just to defend the area. They'd never have the ability to launch raids, or attack at all. This is a fantasy that belies any realistic sense of reality. Japan could at best hold Hawaii for a year before something forced them out.

2) Japan would have used the Naval Yards not just to salvage the sunken fleet, but also to refit their fleet with reverse-engineered radar and other advanced technologies obtained at Hawaii.

They already had radar... They just never put them in their planes which really they couldn't do. There's a reason that the Zero and almost every Japanese plane had nearly no protection and its because of the limited access to metals. You can't build radar without rare earths which Japan didn't have in abundance. They can get the technology but it does them little good. They can't really implement it.

3) The submarine base would have sped up development of the submarine carriers - which would close Panama, preventing any ships, troops, or supplies from moving from the Atlantic to the Pacific, unless the USN was willing to risk the Straits of Magellan.

Why are you obsessed with the absurdity of a submarine carrier? Because you saw it in a cartoon and thought it was cool?

4) Carriers based from Hawaii could launch hit and run strikes against Naval Yards up and down the West Coast with little fear of retribution - the Pacific is vast, and the fleet would have been refitted with radar technology.

No. They couldn't. They really really couldn't. This is a very easy concept to understand. The oil supply at Pearl would be a great steal for Japan but in the end the oil in the SE islands is mostly unobtainable at this time period. The means to extract the oil were limited and Japan only had access to a single refinery at Satsuma. That's 1500 miles that they need to transport an extremely limited oil supply to their own main refinery, and then 3000 more to transport it to Hawaii, another 2000 to get it to the islands of the South Pacific, and another 1500 to get it back to South East Asia. They will burn up, every single once of oil, just moving their limited supply around.

And little fear of retribution? Hello land based airfields loaded with planes.

5) As Baron pointed out, once Pearl Harbor was lost, any ships at sea would have minimal chance to reach the West Coast at all.

They would have just harvested the fuel of smaller ships and would have reached the coast, as he also pointed out (I don't know if that's true I just assume its not made up). Of course, those ships don't exist in a vacuum where losing Pearl means they have no help at all. The carriers and any ships with them could probably at least limp within range of land based ships that could get to them and bring them back before Japan was freed up from Hawaii to retaliate, saving the carriers and keeping them in the pacific.

But this invasion idea is absurd. The operation to attack Pearl was not a secret to the US, it just wasn't taken seriously. We knew their fleet wasn't in port because the US ambassador could see the fleet from the embassy and reported its departure. They kept everything quiet and we assumed it as a training exercise for their fleet. If an entire army, also disappeared with that fleet, it's a massive red flag that something is up and its probable that MAGIC intercepts suggesting an attack would have been taken more seriously. An army cannot disappear and go unnoticed by anyone.

Tadashi wrote:What makes you think Japan wouldn't have improved the design (either of the submarine-carriers or the planes or the weapons) for a sustained effort to keep the Panama Canal closed?

Because its a infeasible design. Why do you think no one operates any submersible aircraft carriers today? Its expensive enough to build a normal carrier, making it submersible is 1 redundant because it doesn't improve its ability to deploy aircraft at all 2 mechanically absurd.

Tadashi wrote:Then capture them...seize Hawaii, suppress the West Coast's shipyards, and close the Panama Canal.

They wouldn't be able to suppress the west coast. They had no planes that could reach that far, and contrary to what some people seem to be thinking about how having oil takes you anywhere you want to go, they would not be able to go another 2000 miles to the US west coast and do anything for very long, let alone all the way to the panama canal and blockade it. Some people in this thread seem to have no idea how much oil you actually need to operate a fleet 5000 miles from home when there is almost no supply to back it up. Japan could never maintain the logistics of such a campaign, they would know that, and they'd never try it. Their Navy was much better in that field than their Army.

sebster wrote:A better hypothetical here would be 'what if the Japanese hadn't been insanely cruel in China?' There was little real support for the warlords of the KMT, and the communists were not at that stage a functioning alternative, so what if Japan had managed to win over the Chinese population. Instead of seeing so many men and resources squandered in China, could a more successful invasion have they instead have gained men and resources, and maybe been in a better position to consolidate their holding in Asia?

That actually is an interesting question. I'd need to look up how Japan felt about the end of the Sino-Japanese war, and the colonial days before the second began. If the Japanese were nicer, my initial thought isn't wide support but that they wouldn't encounter much resistance.

 LordofHats wrote:
Even if the Japanese had achieved their second decisive engagement (say, for instance, that the good luck enjoyed by the US at Midway went the other way), then the Japanese were really hoping that the US would put their tails between their legs and agree to grant the Japanese open season in the South Pacific. Because they certainly couldn't have even pretended at an invasion of mainland USA, so their only hope was that the Americans would just give up and sign a treaty.

And I think we all know that was never going to happen.

Well yeah. Like I said, the advantage of hindsight. In end nothing was gonna win Japan the war. Once FDR got committed it seems he was really committed to victory. Of course, the pointless seizure of Hawaii would only reinforce that outcome.

That's not quite right. The US continued to build battleships through the war. And both sides continued to treat their battleships as key elements of their fleets, and remain wary of the threat of the major capital ships of the other side. It was only really in the aftermath of the war that the aircraft carrier was really acknowledged as the primary element of naval power.

It wasn't a conscious decision on our part its just something that happened. We laid down carriers to expand the fleet and they got finished first and went out to join the fleet before the new battleships were ready. I don't think anyone even considered that this had happened and what it meant until the 70's.

BaronIveagh wrote:No, most likely the surface fleet would have to do the interdicting along the US west coast. It's hard to build ships if your slip ways are covered in bomb and shell craters, and there are a limited number of possible targets. Sen toku class boats were something of a Pie in the Sky idea that might have actually worked. In reality, without a viable US surface fleet, it would have been easier to deploy a squadron of light cruisers and maybe some Kongo class BBs, and shell it back to the stone age.

Its actually not. Once your at war, and with an enemy who has no strategic bombing force and can only engage you with fleet based aircraft, patrol ships can spot their fleet and run away before being attacked and dockyards can be reinforced with AA defense. Flak makes mincemeat of Japanese aircraft in WWII. And since they can't carry any significant ordnance, well...

This of course assumes Japan can launched the attacks. Again, the oil just isn't there. They're fighting too many enemies on too many sides with extremely limited resources. The oil supply couldn't sustain such a war effort, which the staff officers of the IJN would realize and as a result they'd never take that course of action.

In a Japanese invasion scenario, using the 14th Army:

And I suppose there's some logic to support how the Navy and an Army can disappear off communications and not be taken as a sign by anyone with a brain? The disappearance of the Japanese fleet can be overlooked by the unprepared as "meh, its probably nothing" but a fleet and an army, and the amphibious craft to land that army?

 Galdos wrote:
If by superior technology you mean 'scads more of them' sure. If by 'superior technology' you mean a direct ship to ship comparison... no. Further, the Sherman is not an MBT. THe MBT designation for tanks came about long after the Sherman left US service. The M4 was classified as a medium tank, which at the time meant that it was a direct fire support tank for the army. It's astonishingly lackluster ability when faced with contemporary tanks in it's own weight class led to thier nickname. Ronsons.

The Sherman's negative reputation is another advantage we gain from hindsight. It was a highly effective tank, even against its own weight class against Panzer IV's in Europe.

 Galdos wrote:
Well, point of fact, Japan built very few carriers at all between the beginning and end of the war, however the Taiho class had armored decks. Of the US carriers, only Yorktown, Essex and Midway class boats had armored decks.

While the Iowa class battleship was, in many ways, superior to most battleships, Iowa vs Bismark/Yamato class again is much more in doubt. If Japan or Germany had the industrial capability to produce the so called superbattleships and carriers in the sort of quantities that the US did, the US would have quickly lost the war.

That's like saying "if Germany and Japan were anyone else with the ability to maintain a long war effort" at which point what are we really talking about? The reality is that both Japan ad Germany lacked the natural resources to maintain their forces over time.

 sebster wrote:

But if they captured US radar would they have even recognised the value of it? The US regarded it as little more than a toy at the time, despite its successful use by the British in the Battle of Britain. Iit was only in the wake of Pearl Harbour that they realised what might have been averted if they'd taken radar more seriously that they changed. Would the Japanese have seen the radar facility and thought 'here is a technology for telling you where the enemy planes are that we just captured from an enemy who had no idea where our planes were, so it clearly works great and we better spend our limited resources building as much of it as possible.'

Yamamoto would have had them working day and night on it, as it was a technology that would compliment his idea of how carriers and battleships worked together.

Yamamoto unfortunately was not popular with the Japanese government. The officer who represented the Navy in the cabinet actually hated him and was a proponent of big gun ships, like most of the Japanese navy at the time. Yamamoto was popular for his leadership and ability, but he was pretty much alone in his military in terms of naval theory. He had few supports. So while Yamamoto may have realized its value (I'm sure the Japanese in general may have realized its value) that doesn't mean he'd get support for implementing it. Of course, ignoring that the Japanese could not build sophisticated radar systems, let alone to the extend of the USN anyway.

Now cover it in modern CIWS on a rigid airframe with variable prop engines.

Hello missiles. I'm an easy target. Shoot me. Rigid airships might rise again as a means of cheap transport compared to commercial jets, but the military application of a large airship is highly limited.

And no. Drone based doesn't help their case. We have ballistic missile subs now, so if the point is a submersible platform from which to attack a target at range, a missile does the job much better and doesn't force the submarine to surface. A carrier has a highly specialized job: to maintain air support over a region. If this task is to be achieved, it would force any carrier that could submerge itself to remain on the surface for long periods of time to launch and retrieve its aircraft negating the point of being able to submerge. The reality of a carrier is that it gains nothing by being able to go underwater. Likewise, submarines aren't really improved by the ability to launch aircraft. And those both ignore the mechanical complexity of a submersible launch deck.

 Tadashi wrote:
Now you can speculate 'what if the Americans had developed a complete understanding of the cultural differences in the world?' Well then they probably would have developed an understanding of the importance of 'leaving well enough alone', and focused on continuing reform of America's economy, and not gotten themselves involved in a stupid, pointless war in the Middle East.

Besides not being a comparable statement at all, it also has the value of having nothing to do with WWII.

 Tadashi wrote:
That aspect of them would not change.

You still haven't commented on my point that the Japanese command had no consideration for concepts of long term strategic war like that you're planning here. I suspect this is because you don't really like dealing with anything that challenges your idea of a gloriouss Japanese Empire.

 sebster wrote:

 BaronIveagh wrote:
No, most likely the surface fleet would have to do the interdicting along the US west coast. It's hard to build ships if your slip ways are covered in bomb and shell craters, and there are a limited number of possible targets. Sen toku class boats were something of a Pie in the Sky idea that might have actually worked. In reality, without a viable US surface fleet, it would have been easier to deploy a squadron of light cruisers and maybe some Kongo class BBs, and shell it back to the stone age.

Seriously? Direct naval action against major port facilities?

You do know how terrible an idea the allies thought that was, even with the combined might of the Atlantic fleet. And you are aware that planes can take off from land, and make any idea of sitting a boat off the West coast of the USA look incredibly stupid very quickly.

Right...as if the ships would just sit in the same place all the time

Yamamoto would have had them working day and night on it, as it was a technology that would compliment his idea of how carriers and battleships worked together.

You make that sound as if Yamamoto would have been magically, instantly aware of the capabilities of the technology, which is a massive stretch given the reason I already stated - people do not see the power of a technology that the only captured because the enemy failed to use that technology at all.

Why not? The man was a genius.

 sebster wrote:

 Tadashi wrote:
That aspect of them would not change.

You still haven't commented on my point that the Japanese command had no consideration for concepts of long term strategic war like that you're planning here. I suspect this is because you don't really like dealing with anything that challenges your idea of a gloriouss Japanese Empire.

Why should I? Especially when most people from the USA tend to avoid the dirt the US government's been sweeping under the carpet ever since your upstart nation came into being?

 Tadashi wrote:
Why not? The man was a genius.

That isn't how genius works. Being a brilliant strategist doesn't make one suddenly an engineer, and vice-versa.

 Ahtman wrote:

 Tadashi wrote:
Why not? The man was a genius.

That isn't how genius works. Being a brilliant strategist doesn't make one suddenly an engineer, and vice-versa.

But it would certainly allow him to see the advantages of such a system.

 Tadashi wrote:

 Ahtman wrote:

 Tadashi wrote:
Why not? The man was a genius.

That isn't how genius works. Being a brilliant strategist doesn't make one suddenly an engineer, and vice-versa.

But it would certainly allow him to see the advantages of such a system.

If they knew what it was and how it worked, which at the time, they did not. It wasn't like they had a chance to observe it in action. He couldn't place his hands on it and by osmosis suddenly understood it's functions and capabilities. I'm not a military genius and I can tell you the advantages of such a system once it's capabilities are known.

 Tadashi wrote:
Especially when most people from the USA

I wouldn't trust your judgement on small groups of people in the USA, let alone silly statements about 'most'.

Tadashi wrote:Right...as if the ships would just sit in the same place all the time

When launching aircraft in WWII, actually you'd be surprised. A fleet can't move very far in a few hours and really shouldn't if it expects its aircraft to come back. Add in that US aircraft had longer ranges than Japanese, and the advantage of land based fields.

Why not? The man was a genius.

Doesn't make him magic.

 Tadashi wrote:


Why should I? Especially when most people from the USA tend to avoid the dirt the US government's been sweeping under the carpet ever since your upstart nation came into being?

Because reality and fantasy are very different things, and that's not really a reason to avoid reality. It's just snippy

 Tadashi wrote:
But it would certainly allow him to see the advantages of such a system.

I think you're trivializing him too much. Yamamoto wasn't magic. He was certainly more correct about the future of naval warfare than his contemporaries in the IJN, but he was actually very wrong about a lot of things. He didn't think submarines were that useful as a weapon, and believed that big gun ships would still be needed to support a naval air arm, which... They aren't. That said, his plans weren't flawless either.

 Ahtman wrote:

 Tadashi wrote:

 Ahtman wrote:

 Tadashi wrote:
Why not? The man was a genius.

That isn't how genius works. Being a brilliant strategist doesn't make one suddenly an engineer, and vice-versa.

But it would certainly allow him to see the advantages of such a system.

If they knew what it was and how it worked, which at the time, they did not. It wasn't like they had a chance to observe it in action. He couldn't place his hands on it and by osmosis suddenly understood it's functions and capabilities.

Uh-huh...as if acquiring the device and not looking for the instruction manual or something along that line is how Naval Intelligence works.

 Ahtman wrote:


I wouldn't trust your judgement on small groups of people in the USA, let alone silly statements about 'most'.

The fact your government can and does certain things in a similar manner to what dictatorships do, indicates a critical flaw in your 'democratic' system.

 Tadashi wrote:
Uh-huh...as if acquiring the device and not looking for the instruction manual or something along that line is how Naval Intelligence works.

Believe it or not, the men operating radar stations on Hawaii, actually didn't even understand how to turn them on!