Well to be honest, I'm really just trying to play devil's advocate here. I agree that Cap is a likely candidate, but I don't think "believing in America" automatically excludes most others.
I certainly consider gray personalities like Hawkeye less suspect, but I think Widow should be seen past her "commie slut" exterior. On the other hand, Millar hasn't really built her up as a character either, but that's just me playing devil's advocate with myself---which will only guarantee an endless series of circular arguments that could never fit into one post.