Wait. Captain America IS a mutant, just not naturally. Hulk as mutant as well. Thor... well, he's ALIEN!!! And from the experiences of alien encounter in Marvel universe, all aliens are invaders. Now go and try to explain them, that one alien protects you from another...
And keep in mind, that what we know, is not necessary what the Marvel Earth citizens know. They probably can't tell the difference between Iron Man and Hulk, and might think both as mutants. They probably don't know what SHIELD is, but they do see the Avengers fight enemies on the streets. And then they see Magneto with his mutants.
Anyway, I get the point, I don't read comics, I watch movies, where many things are not shown. But Marvel can't expect everyone to go into comics and seek answers for their question from there. It is a good thing, but not everyone will do that.![]()
Wow wow wow. Tony Stark (even in the movies) is FAMOUS and EVERYONE knows it's just a dude in a suit.
Captain America isn't a mutant. Mutants are created by evolution (google it). Captain America is genetically enhanced. Hulk, also is genetically enhanced (alas he failed in his final outcome).