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 Peregrine wrote:
it was their arrogance in their god-like status that made the primarchs targets in the first place.

The Chaos Gods scattered the Primarchs before they were "born".

 Gael Knight wrote:

 Peregrine wrote:
it was their arrogance in their god-like status that made the primarchs targets in the first place.

The Chaos Gods scattered the Primarchs before they were "born".

Well yes, they made themselves targets and Chaos attacked the target. First Chaos scattered them, and then Chaos whispered dark secrets and promises of power to them. And half the space marines eagerly betrayed their Emperor, nearly destroying humanity in the process.

You're doing a very poor job at proving that Astartes don't matter.

Seeing as they are in every war of consequence for the Imperium.

The point earlier about space marine autonomy is dead on the money; in 40K, having your own fleet is EVERYTHING.

By design, all branches of the Imperium, with the exception of space marines and adeptus mechanicus MUST rely on the navy to get anywhere; the navy, in turn cannot occupy and capture planetary assets without ground troops.

The guard, no matter how powerful, can only ever impact the planet they are on, unless the navy gives them a ride. Ditto for knights, custodes, sisters, ministorum and the inquisition (though these guys, theoretically have the authority to commandeer EVERYTHING in the Imperium under certain circumstances, so the lack of a fleet isn't really an issue).

And as for the Heresy, the fact that marines started the trouble actually increases the importance of the marines, rather than diminishing it. "Important" does not imply a position on the moral spectrum, and therefore the loyalist/ traitor dichotomy is irrelevant to the question.

It is, however, a total overstatement to suggest that they were a part of every battle of consequence. The first contact events with both the tyranids and necrons were obviously battles of consequence, and neither involved marines. Tyranids have devoured hundreds of worlds that never saw an imperial presence, let alone a marine, and a battle that turns a planet into a barren rock should certainly constitute a battle of consequence.

Now of course, you can redefine "battle of consequence" to exclude battles that didn't include the imperium at all, and then your statement would be closer to the truth. You could also redefine it to include only imperial victories, and that might be closer to the truth, but I'd have to do more research to assert that for sure.

Similarly, you could redefine "battle" to campaign or war, and that would also bring the statement closer to the truth.

Finally, regarding "chaos would have still found a way to screw the universe," that is absolutely true. The birth of slaanesh had nothing to do with the imperium at all, and if I'm not mistaken, that was also the birth of the eye of terror. Even if you restrict the corruption to the Imperium, it still happens again during the Age of Apostasy (obviously many of those battles did involve marines; the point I'm making here is that the age of apostasy would have been the imperium breaking event in a timeline that didn't include the horus heresy).

PS- Sorry to grind semantics and write paragraphs- I'm just bored.

Space Marines are the rapid response force. The imperial guard takes a long time to mobilise into the kind of overwhelming numbers needed to swamp the opponent. And even if they did, then they would probably be led by the chapter masters of the space marine chapters that would probably also arrive to lend a hand.

Its all about relative numbers. Space marines were broken up into chapter strength so that they could never again threaten the imperium the way the horus heresy did. Even so, just one renegade chapter going rogue has ever swamped a whole system into flames.

Imagine if you could put together hundreds of thousands of space marines into a legion of old. They would be an unstoppable force. You can put 2 million guardsmen on a planet in several months or a year of deployment. Before half are even deployed, several hundred thousand space marines would have already deployed there, and destroyed or taken all possible landing sites. It would be a massacre.

Comparing the quality of a few space marines against one thousand guardsmen is of course redundant. But what if I could deploy five hundred thousand space marines onto that battlefield in half the time you could take to deploy 1 or 2 million guardsmen?

That's why the horus heresy showed how dangerous space legions were when they were used as a weapon against the imperium. Horus came close to toppling to imperium.

Small numbers of space marines are of course not a threat. But once you can gather legion strength numbers of space marines, its a totally different ball game. With their flexibility, equipment, rapid deployment ability, a legion of space marines is far far more dangerous than a cumbersome big army of guardsmen. Especially when the theatre of battle allows for only more limited numbers.

Like imagine city block urban fighting. Except every opponent you face is a space marine while your side has only guardsmen. The casualties on the guard side will be horrendous. Now you could have maybe far more guardsmen. But in the tight quarters of urban fighting, all those bodies will just get in the way.

Quality on its own is of course not useful if outnumbered by so much. But once you have enough absolute numbers, then quality makes a big big difference. So, yeah. a squad or two of space marines are not going to achieve much. But a few hundred thousand space marines in legion strength? That can and would be a huge threat to just about anything, even a big guard army.

And BTW, space marines DO still gather in legion strength. Black legion does that all the time in the black crusades.

Yeah, it's one of the things in 40K fluff that really stretch my suspension of disbelief. If it were 1Mio. Marines in every Chapter I could unterstand their importance. And then something like 200Mio. Marines per Legion during the Great Crusade? Okay, yeah, that could probably conquer several planets at once if supported by billions of guardsmen.
But merely 1000Marines? And more often than not they're even less, I wonder how that tiny, ridiculously small number of Blood Angels could do anything on Baal against the Tyranids.

 Gael Knight wrote:
Seeing as they are in every war of consequence for the Imperium.

Only because I know you're going to define "war of consequence" in a way that only includes wars where space marines are present. And surprise, surprise, in most of the wars that GW publishes anything about they include the designated face of the IP.


Automatically Appended Next Post:

Eldenfirefly wrote:
Before half are even deployed, several hundred thousand space marines would have already deployed there, and destroyed or taken all possible landing sites.

I don't think you understand the scale of a planet. The D-Day landings in France involved 150,000 soldiers, all for a tiny area of land in one small country. On the scale of a planetary war even hundreds of thousands of troops is a small amount, and 500,000 space marines would be spread out across an immense area. The 1-2 space marines guarding each potential landing site could be easily overwhelmed by a mass attack.

But what if I could deploy five hundred thousand space marines onto that battlefield in half the time you could take to deploy 1 or 2 million guardsmen?

Then 1-2 million guardsmen are attacking each of hundreds of other targets, none of which are defended by space marines. Even if the space marines win the battle and miraculously avoid taking excessive losses they still lose the war.

Also, 500,000 space marines is half the space marines in the entire galaxy. Right there is the ultimate concession of how useless they are. Deploying half the Imperium's entire space marine forces, an unprecedented scale of use, is maybe sufficient to win one battle in a war while conventional forces win the war everywhere else.

Like imagine city block urban fighting. Except every opponent you face is a space marine while your side has only guardsmen. The casualties on the guard side will be horrendous. Now you could have maybe far more guardsmen. But in the tight quarters of urban fighting, all those bodies will just get in the way.

Until the attacker says " this" and just bombs the city off the map. At which point the attacker has failed to capture the city intact, an objective that was probably not going to happen anyway once that level of fighting started, but the losses in space marines are almost certainly an unacceptably high price to pay for that minor victory.

If you want a perfect illustration of the ridiculeness of the numbers of Space Marines, take Cadia. It's a planet of 850 million person, so not all that much. It has a population comparable to that of humanity during the Bronze Age. It's said that 72% of its population is a member of the PDF of the planet which are trained from early infancy. For this planet alone, there is 62 soldiers for each Space Marines. Armageddon is supposed to have a population 150 billions and has about 10% of its population conscripted in the Steel Legion. That's 15 billion guardsmen 1500 guardsmen for each Space Marine in the galaxy. If all the Space Marines were on Armageddon, they would have an impact comparable to about 60 Navy Seals next to the entire US military combined (national guard not included). Could they be useful? I completely agree, could we do without them. Absolutely. Now imagine a million more world beside those two. Some of them probably only have a few thousand soldiers on them, but there are other Hive Worlds and other Fortress World that produced trillions of guardsmen.

One 1000 marines per chapter is and always has been bs.

With a force of only a thousand space marines of which each marine takes YEARS to develop and train losing more then 10 marines in an engagement would be a crippling blow.

Carefully targeted artillery can destroy specific targets without reaching exterminatus levels of destruction. If you can aim a marine drop pod at an enemy commander you can demolish the building with artillery and leave the rest of the area untouched.

... are you serious? its the imperium, there is no such thing as "accurate artillery" in the manner your claiming, your doing that thing you do all the time, trying to equate real life with 40k.

{citation needed}

Just what exactly are these enemies that are immune to normal humans using plasma guns/lascannons/etc, but vulnerable to a bunch of screaming idiots in power armor using the same weapons?

Strawman fallacy, you are asserting that lascannons etc. dont work to create a counter argument for an argument I am not making,

As for Citations for forces which numbers wont win the day alone, Orks, Tyranids, Death guard (plague war shows this very well), drop pod assault by space marines haha.





Automatically Appended Next Post:

Sgt. Cortez wrote:
Yeah, it's one of the things in 40K fluff that really stretch my suspension of disbelief. If it were 1Mio. Marines in every Chapter I could unterstand their importance. And then something like 200Mio. Marines per Legion during the Great Crusade? Okay, yeah, that could probably conquer several planets at once if supported by billions of guardsmen.
But merely 1000Marines? And more often than not they're even less, I wonder how that tiny, ridiculously small number of Blood Angels could do anything on Baal against the Tyranids.

Honest answer is because that is what the universe says can be done, lets say for arguments sake that it were true and we put them in the real world, as in we took marines as they are in the fluff with the crazy abilities and feats they have pulled off and transfered them to the real world, from our perspective its impossible, utterly impossible for 100 marines to take a planet, until they do it, suddenly we would change our tunes.... waffling over.

As others have said, the autonomy and ability to rapidly respond is the main draw of the Astartes. The glacial speed of the Administratum, responsible for every major deployment of Imperial military and naval assets, cannot be understated. This bureaucratic monstrosity will bring overwhelming force to bear eventually, but all too often it will be too late. Even Scions, the Special Forces of the Guard, will not be deployed quickly. Tactically they excel at rapid deployments, but it may take years of logistical preparation to even get them to relevant the campaign zone. The Imperium would disappear overnight without the Imperial Guard, but without the Astartes the already slow to react forces of mankind would be slower still.


While I don't think even a Chapter-scale deployment should ever be enough to conquer a moderately populated planet by themselves, Marines work well in tipping the balance in the Imperium's favour at precise points and with lethal suddenness that the Imperium is otherwise completely incapable of. As others have pointed out, there are also foes of a type completely inimical to regular combat against mortal, sane opponents.

 Formosa wrote:
... are you serious? its the imperium, there is no such thing as "accurate artillery" in the manner your claiming, your doing that thing you do all the time, trying to equate real life with 40k.

Where did you get that artillery in 40K was less accurate then our own? thousand basilisk were used to destroyed a Warlord Titan kilometers away in the fluff. In one of Gaunt's Ghost novel, they use a single shot from a ship's cannon to kill a greater daemon, destroying about a hundred meters of storage facility in the process. No guardsmen were killed. That's pin point precision. Precise artillery fire isn't complicated. You just basic algebra to do it. Launching a drop pod requires more extensive and complex maths.

epronovost wrote:

 Formosa wrote:
... are you serious? its the imperium, there is no such thing as "accurate artillery" in the manner your claiming, your doing that thing you do all the time, trying to equate real life with 40k.

Where did you get that artillery in 40K was less accurate then our own? thousand basilisk were used to destroyed a Warlord Titan kilometers away in the fluff. In one of Gaunt's Ghost novel, they use a single shot from a ship's cannon to kill a greater daemon, destroying about a hundred meters of storage facility in the process. No guardsmen were killed. That's pin point precision. Precise artillery fire isn't complicated. You just basic algebra to do it. Launching a drop pod requires more extensive and complex maths.

Which 40k book was that??? and the second one, which book was that too?

And where do I get it, so far I have see no evidence that 40k artillery is accurate on the scale of ours, you pointing this out is literally the first example I have ever even heard of, not saying I dont believe you are anything but I will have to read it for myself.

Every example I have ever seen of 40k artillery is that it is utterly indiscriminate, point in general direction of enemy and fire, also I have never seen any example of targeting equipment etc. on artillery platforms, I have seen it a couple of times for Leman russ and other vehicles, but never Basilisk etc.

 Formosa wrote:

epronovost wrote:

 Formosa wrote:
... are you serious? its the imperium, there is no such thing as "accurate artillery" in the manner your claiming, your doing that thing you do all the time, trying to equate real life with 40k.

Where did you get that artillery in 40K was less accurate then our own? thousand basilisk were used to destroyed a Warlord Titan kilometers away in the fluff. In one of Gaunt's Ghost novel, they use a single shot from a ship's cannon to kill a greater daemon, destroying about a hundred meters of storage facility in the process. No guardsmen were killed. That's pin point precision. Precise artillery fire isn't complicated. You just basic algebra to do it. Launching a drop pod requires more extensive and complex maths.

Which 40k book was that??? and the second one, which book was that too?

And where do I get it, so far I have see no evidence that 40k artillery is accurate on the scale of ours, you pointing this out is literally the first example I have ever even heard of, not saying I dont believe you are anything but I will have to read it for myself.

Every example I have ever seen of 40k artillery is that it is utterly indiscriminate, point in general direction of enemy and fire, also I have never seen any example of targeting equipment etc. on artillery platforms, I have seen it a couple of times for Leman russ and other vehicles, but never Basilisk etc.

That's because usually there's no NEED for pinpoint precision. The enemy is there-where? ALL THERE. FIRE EVERYWHERE.

But, despite the Imperium having DEFINITELY backslid from their technological height of 30k, they're still a LOT more advanced than we are today.

 Formosa wrote:

epronovost wrote:

 Formosa wrote:
... are you serious? its the imperium, there is no such thing as "accurate artillery" in the manner your claiming, your doing that thing you do all the time, trying to equate real life with 40k.

Where did you get that artillery in 40K was less accurate then our own? thousand basilisk were used to destroyed a Warlord Titan kilometers away in the fluff. In one of Gaunt's Ghost novel, they use a single shot from a ship's cannon to kill a greater daemon, destroying about a hundred meters of storage facility in the process. No guardsmen were killed. That's pin point precision. Precise artillery fire isn't complicated. You just basic algebra to do it. Launching a drop pod requires more extensive and complex maths.

Which 40k book was that??? and the second one, which book was that too?

And where do I get it, so far I have see no evidence that 40k artillery is accurate on the scale of ours, you pointing this out is literally the first example I have ever even heard of, not saying I dont believe you are anything but I will have to read it for myself.

Every example I have ever seen of 40k artillery is that it is utterly indiscriminate, point in general direction of enemy and fire, also I have never seen any example of targeting equipment etc. on artillery platforms, I have seen it a couple of times for Leman russ and other vehicles, but never Basilisk etc.

The Basilisk entry is from one of the earlier IG codexes. Though when you're firing several thousand artillery pieces at a Titan-sized target for days on end chances are a portion of them are going to hit, so it doesn't necessarily mean pinpoint accuracy but it does indicate that it's not wildly inaccurate to the point of being unable to single out significant targets.

 Formosa wrote:
Which 40k book was that??? and the second one, which book was that too?

The first one was in a codex if I'm not mistaken, the 5th eddition one for the Imperial Guard. The second was in the first omnibus of the Gaunt Ghost (I think it's in the second book).

so far I have see no evidence that 40k artillery is accurate on the scale of ours, you pointing this out is literally the first example I have ever even heard of, not saying I dont believe you are anything but I will have to read it for myself.

Every example I have ever seen of 40k artillery is that it is utterly indiscriminate, point in general direction of enemy and fire, also I have never seen any example of targeting equipment etc. on artillery platforms, I have seen it a couple of times for Leman russ and other vehicles, but never Basilisk etc.

Basilisk can hit a target up to 15 kilometers away, but require spotters and trained artillery officers to fire undirectly to the enemy. The Imperium uses all the types of artillery we use today from heavy artillery pieces like the Earthshaker cannon, passing by guided missiles like the Manticore or hunter-killer missiles, to heavy mortars like the Griffon (and even repeating mortars, a thing we don't have, with the Wyvern) to intercontinental ballistic missiles like the Deathstrike missiles. I don't see how an army capable of firing intercontinental ballistic missiles would fail direct artillery fire competently and hit a 100 meter wide zone. This assumption artillery fire cannot be very precise seems to some out of nowhere.

If you read some Battlefleet Gothic material there are several stories on how a rebellion was stopped by a single shot from a ship destroying the palace and fortress where the traitors command center was situated. You read about what GW sells. If they sell you commandos in power armor, of course they won't masturbate over the power and precision of artillery. Artillery is boring, but its the deadliest weapon by far in any war.

One of the things that may make marines seem useless is the disparity between the background and 'standard' games of 40k.

In the game, space marines are deployed as an army against an even force. In the background they are used for decapitation strikes and sabotage.

We don't hear the stories where the space marines aren't needed (the rebel commander forgot to shield his base from orbital strike). We hear the ones where a small group of marines made able to turn a few key battles to win a war.

40k =/= real life


Basically the background of 40k is like action movies, youll watch it and like ( or not ), but there is no historical correct re-enactment, just entertainment..

Arguments of scale are set to fail.
Consider this: soo many space orks vs soo few space elfs. => space elfs don't matter, so kick them out and stick with the space orks

They’re there to behead the beast.

They can strike pretty much wherever they want. They take a helluva lot of stopping. Their weapons are based on ‘one hit, one kill’.

They’re who you shove right down the gullet of the enemy command structure, and they gut it completely.

Orks, Eldar, Renegades, Tyranids, Necrons. All have the same weakness, to one degree or another. Take out the head honcho, and things start going wrong for them.

That is what Marines are for.

Related question: How many Necrons are in your average Tomb World? And of what types?

 JNAProductions wrote:
Related question: How many Necrons are in your average Tomb World? And of what types?

Billions, at least 90% are simple Necron Warriors why?

It really depends on how accurate book marines are vs game marines.

In game, a marine really isn't that much better than a regular human in strength or survivability. In book though, they're significantly stronger.

Where Marines make a lot of sense, in my opinion, is when you think about interstellar conquest. transporting and supplying a billion man army of guardsmen is going to be a nightmare, regardless of whether you have them men or not. You can't just dump a billion dudes with lasguns and flak jackets on a planet and think you're going to succeed. but deploying 1000 supermen out of a small strike fleet would be quite plausible. I see it playing out as follows.

1) Human planet identified by rogue traders.
2) Imperial diplomats and espionage agents engage locals.
3) Locals refuse annexation.
4) A single marine strike fleet arrives, and blows the local SDF out of space.
5) 100 super humans drop pod directly into the planetary government building and butcher everyone. A thunderhawk blasts its way through their air force and recovers the marines before the ground forces can respond.
6) The marines repeat this until a local government surrenders.

Against normal humans, the marines will generally be able to strike where they want and escape before any kind of response can be assembled, as long as they control the local air space via thunderhawk and space based support.

After enough of this shock and awe, the leadership of the planet will generally surrender. This same procedure would also work very well against rebel planets.

Where marines make less sense is in grinding warfare, unless you're going by Movie Marines, such as Relic's Space Marine. Marines need to get in an out fast, before the opposition can retarget them with artillery or missile strikes.

epronovost wrote:

 JNAProductions wrote:
Related question: How many Necrons are in your average Tomb World? And of what types?

Billions, at least 90% are simple Necron Warriors why?

How many Warriors are worth one Marine?

Because there are one million Marines. That’s at least a 1,000 to 1 ratio of Warriors:Marines.

 Talizvar wrote:
IG/AM guard are numbered in insane quantities, they almost literally bury the enemies of the Imperium.

Think of the ratio this way:
472,000 active personnel in the USA Army.
184,000 in the Marine Corps.

About 2.5 to one.

The idea is rapid deployment, a forward unit able to deploy from a variety of platforms in conjunction with other military arms of government.

If you want it down to a tiny blurb: The difference between Quantity and Quality.

They ARE representative because of course every battle you play is IMPORTANT so of course the Space Marines will be there!

The USMC are not special forces. They are specialIZED forces. Do not use this comparison for Guard and Space Marines.
Tempestus Scions are what Special Forces are to real armies, Space Marines are just Specialer Forces. There is nothing in the real world usable for a decent comparison.
SM simply have a different field of use than the Guard. Deploy the Guard and you fight for a long time with a lot of collateral damage. Deploy the Space Marines and you don't fight as long and with
the collateral damage confined to a much smaller area.

 Formosa wrote:

Sgt. Cortez wrote:
Yeah, it's one of the things in 40K fluff that really stretch my suspension of disbelief. If it were 1Mio. Marines in every Chapter I could unterstand their importance. And then something like 200Mio. Marines per Legion during the Great Crusade? Okay, yeah, that could probably conquer several planets at once if supported by billions of guardsmen.
But merely 1000Marines? And more often than not they're even less, I wonder how that tiny, ridiculously small number of Blood Angels could do anything on Baal against the Tyranids.

Honest answer is because that is what the universe says can be done, lets say for arguments sake that it were true and we put them in the real world, as in we took marines as they are in the fluff with the crazy abilities and feats they have pulled off and transfered them to the real world, from our perspective its impossible, utterly impossible for 100 marines to take a planet, until they do it, suddenly we would change our tunes.... waffling over.

Yeah, I agree with you. I always tell a guy in our gaming group, who really dislikes Marines and basically only knows their tabletop performance and wonders why they seem that important in the fluff, that one has to imagine every single marine as an Avenger. A marine with jump pack is iron man, a marine with lightning claws is wolverine, A terminator with hammer is the Hulk and so on. With that in mind I could imagine 100 super heroes to conquer a planet or at least take out an enemy HQ in no time.
The problem is, that even in 40Ks fluff marines are often not portrayed that way. Instead they're holding the line in some trench, get overwhelmed by Ork boyz or get shot to pieces by some dangerous xenos gun. Like the whole imperial fists chapter gets destroyed by the first attack wave of the Orks when the Beast arises. Or in the case of Chaos Marines get fought off with bayonets of the imperial guard (see Dark Imperium). Or when a Blood Angels squad gets eaten by Tyranids like redshirts just for the lolz because the writer wanted to quote Aliens (see that one short story I forgot the name of). And that's where I start to doubt their importance.

 Peregrine wrote:

I don't think you understand the scale of a planet. The D-Day landings in France involved 150,000 soldiers, all for a tiny area of land in one small country. On the scale of a planetary war even hundreds of thousands of troops is a small amount, and 500,000 space marines would be spread out across an immense area. The 1-2 space marines guarding each potential landing site could be easily overwhelmed by a mass attack.

Peregrine likes real world v 40k.
If it was d-day they just get 1 or 2, maybe a squad of marines to defend those bridges. If they even bothered.
Marines would prolly laugh at the d-day landings. Theyd drop a squad or 2 right on the Reichstaag, turn up kick Hitler and everyone within 1km in the balls, with a angry boot and say whos next, way back in 40.
If you think Himler or Borman are going to say woohoo, im in charge, after that your dreaming.


Ive fooked that format up somehow.

 JNAProductions wrote:

epronovost wrote:

 JNAProductions wrote:
Related question: How many Necrons are in your average Tomb World? And of what types?

Billions, at least 90% are simple Necron Warriors why?

How many Warriors are worth one Marine?

Because there are one million Marines. That’s at least a 1,000 to 1 ratio of Warriors:Marines.

Considering how tough Necron Warriors are supposed to be and how powerful their weapons are, 5-10 per Marine top I would say.

the ancient wrote:

 Peregrine wrote:

I don't think you understand the scale of a planet. The D-Day landings in France involved 150,000 soldiers, all for a tiny area of land in one small country. On the scale of a planetary war even hundreds of thousands of troops is a small amount, and 500,000 space marines would be spread out across an immense area. The 1-2 space marines guarding each potential landing site could be easily overwhelmed by a mass attack.

Peregrine likes real world v 40k.
If it was d-day they just get 1 or 2, maybe a squad of marines to defend those bridges. If they even bothered.
Marines would prolly laugh at the d-day landings. Theyd drop a squad or 2 right on the Reichstaag, turn up kick Hitler and everyone within 1km in the balls, with a angry boot and say whos next, way back in 40.
If you think Himler or Borman are going to say woohoo, im in charge, after that your dreaming.


Ive fooked that format up somehow.

this, people need to stop thinking of space marines as conventional soldiers they're used to apply precise military force and pressure at specific targets, aimed at shattering the enemythe guard can then mop up


Automatically Appended Next Post:

Sgt. Cortez wrote:

 Formosa wrote:

Sgt. Cortez wrote:
Yeah, it's one of the things in 40K fluff that really stretch my suspension of disbelief. If it were 1Mio. Marines in every Chapter I could unterstand their importance. And then something like 200Mio. Marines per Legion during the Great Crusade? Okay, yeah, that could probably conquer several planets at once if supported by billions of guardsmen.
But merely 1000Marines? And more often than not they're even less, I wonder how that tiny, ridiculously small number of Blood Angels could do anything on Baal against the Tyranids.

Honest answer is because that is what the universe says can be done, lets say for arguments sake that it were true and we put them in the real world, as in we took marines as they are in the fluff with the crazy abilities and feats they have pulled off and transfered them to the real world, from our perspective its impossible, utterly impossible for 100 marines to take a planet, until they do it, suddenly we would change our tunes.... waffling over.

Yeah, I agree with you. I always tell a guy in our gaming group, who really dislikes Marines and basically only knows their tabletop performance and wonders why they seem that important in the fluff, that one has to imagine every single marine as an Avenger. A marine with jump pack is iron man, a marine with lightning claws is wolverine, A terminator with hammer is the Hulk and so on. With that in mind I could imagine 100 super heroes to conquer a planet or at least take out an enemy HQ in no time.
The problem is, that even in 40Ks fluff marines are often not portrayed that way. Instead they're holding the line in some trench, get overwhelmed by Ork boyz or get shot to pieces by some dangerous xenos gun. Like the whole imperial fists chapter gets destroyed by the first attack wave of the Orks when the Beast arises. Or in the case of Chaos Marines get fought off with bayonets of the imperial guard (see Dark Imperium). Or when a Blood Angels squad gets eaten by Tyranids like redshirts just for the lolz because the writer wanted to quote Aliens (see that one short story I forgot the name of). And that's where I start to doubt their importance.

next time your IG player complains challange him to a game under your conditions. the conditions will be...

1: he may not take any dedicated anti-heavy infantry weapons. he takes flamers instead of plasma guns, heavy bolters and lascanons for his heavy weapons etc.
2: you may deploy your entire force via drop pod. on turn op
3: the game will not be balanced along points. (I'd give him a 3 to 1 troop ratio over you though as that's about the diff in SM vs IG company sizes)
4: he must conceed the game once his command units are destroyed.

because thats how space marines are gonna play. they'll come in fast, ahrd annialate key command elements and then the IG sweeps in. 40k just poorly reflects the differing doctrines of some races and tends to favor a stand up fight.

I’m sorry, 3:1 Guard to Marine ratio? If he has nothing but officers, sure, but there are one million marines total.

Individual planets have way more Guardsmen than that. By a massive margin.

They only matter in 40K's fiction. They clearly don't matter on the table top. Everything about them is fueled by deus ex machina. They should have left them as space cops.