Is that perception why everyone online constantly shits on America and proclaims that every other country is superior? For as much as people like to accuse Americans of being "'Merica, fuck yeah!" the truth sure looks like it is mostly other countries with the arrogant attitude.
Interesting that the self-loathing seems to be associated with waging unpopular and losing wars. I didn't live through it but the Vietnam War seemed to have some similar impact that persists to this day with the utter loathing of conscription. It seems to be the same underlying cause: that bad leadership essentially permanently burned credibility for their country for no gain for their country.
