[PapaBear3625]

Teeney spoiler here: The movie adaptation has the Avengers team being required to register and become subject to the orders of a UN group, due to all the ancillary damage caused by their escapades in Avengers, Winter Soldier, and Age of Ultron. I won't give any more away, but let's just say that Iron Man and Captain America each had very personal reasons for agreeing to (Iron Man) and not agreeing to (Cap) register.

In real life, it would have gone something like this:

"Iron man, you are operating a flying suit, without FAA certification, in populated areas. Your suit is also equipped with destructive devices without BATF licenses. You will surrender your weapons or face fines that will leave even YOU bankrupt, plus imprisonment. And, by the way, the lawsuits over the damage caused by your creation, Ultron, will mean that you no longer have any money"

"Captain America, that shield of yours is US government property. Hand it over. Other than that you are just an extremely physically fit human. You are free to go."

[freefdny]

“Captain America, that shield of yours is US government property. Hand it over. Other than that you are just an extremely physically fit human. You are free to go.”
That’s pretty much right out of the movie.