What is the appeal of Captain America?

Erik Twice wrote: One could say a lot about the whole American nationalist angle but I haven't found it too bothersome in the MCU, which is my only contact with Marvel.

Straight up -- I think us Americans don't see him as that much of a nationalist, at least not in the films. He's more of a general goody-two-shoes. Short of the uniform he really doesn't project 'Murica very much at all. Given the fragile state of American politics I think the producers have wisely walked a very careful line on the subject.

I'd be curious to hear other Americans' opinions on this.

I agree. As an American, I think it has much less to do with any patriotism as it is the idealized representation of "good" that he portrays, especially in the films. Like someone said above, kinda like Superman without god-like powers.

When Marvel Comics first started publishing in the '60s, superheroes tended to be generic paragons of goodness, nearly devoid of personalities or foibles. Aside from specific superpowers and costumes, they tended to be readily interchangeable and predictable. Marvel heroes were different. They had personalities and often very real weaknesses or even actual handicaps. When Captain America was brought back (from his previous existence in Timely and Atlas comics), he was initially portrayed as a throwback to the iconic style of previous heroes, a paragon without weaknesses. He gradually became more of a Marvel hero, expressing doubts and worries about his leadership, survivor's guilt over Bucky's death, and the occasional awareness that he was a man of a different time and culture. At the same time, Cap also developed into his modern form, as a earnest, idealistic symbol of freedom, as well as master tactician and charismatic leader.

Cap also is an interesting representation of America's struggle with racial issues. He is initially blind to racism and even battles fight some villains that represent some offensive Asian stereotypes. But during the long Englehart run of the '70s, Cap takes on a black sidekick (the Falcon) who eventually becomes more of an equal partner after quite a few serious conversations about their respective roles in society. For most of that era, the comic was even titled Captain America & the Falcon.

America has always been a flawed country, consistently falling short of some very high ideals. Captain America has generally been more representative of those high ideals than the disappointing reality of America. I think that idealism is the crucial to the appeal of Captain America. Much of the world looked to America with admiration after World War II, for our decisive role in victory but also in the humane uplifting of our fallen enemies after the war. Cap comes from a time when America was at peak popularity, and when the shine came off during Watergate, he discarded the costume for a time, though continuing the good fight.