You're being sarcastic, right?
As it pertains the to things unions were orignally intended to protect against, the government HEAVILY regulates.
And lately, the government has been increasing regulation (or trying to) to further "protect the citizen from themselves." See: Banking, Bloomber's various regulations and bans, etc.
IMO, many of the unions that still function exists because they're a part of the status quo and new employees don't feel like they have an option to work in those industries without being in the union.