Have many time has Captain America been disowned by his own country (in the fiction at least). Cap's Mission may not always been in line with State Policy.
As for what Darth mentioned. I agree. But there is always a sense of resentment for those being aided that they are being helped by an American/Singaporean/Malaysian/Venezuelan/Russian etc etc...I was in Aceh post-Tsunami when I was still in the service. The people are always initially grateful for ANY help. But as the grimness of the situation draws on and all they see are photographers, soldiers and dead bodies, the sight of flags of any country gets annoying.
My Medical Officer had to take a picture with a kid for one of our magazines. He was immunizing the boy while the mother was there all silent like and the photojournalist was there snapping away, making sure she got all the right angles, especially the Singapore flag velcro-ed under his Medic patch. The mother started complaining in Bahasa that we were all here (in Aceh) for show and that nobody really cared about the plight of the people there.
I'm not sure how to interpret that. Is flag-waving during humanitarian aid really helping the situation? Or is it just to show the world "Hey! Look we're helping!".