@Invictus. The thing - I believe - is not about choosing between "USA can do no evil" and "USA can do no right", but about having a less ideological and more historiographical view to the events of the past.
I have the impression that this - for the average USA citizen - roughly translates with "coming out of the fairy tale in which USA are good and generous and face the not-always-nice-looking reality".
The US mainstream opinion about itself and its role (both present role and the one had during the WWII) has been affected for decades by ideology, and ideologies - as we know - are dangerous, deforming lenses through which observer the reality.
There are several elements that contributed to building and reinforcing the ideology of the USA. I never studied the issue, but off the top of my head:
1. A partial understanding (with overestimation) of the role of USA in the WWII in Europe: USA public opinion seem to acknowledge very little the role of European resistance and to totally forget the role of Russia and China. For example, USA counted less than 500.000 deaths in the conflict. Both CCCP and China are well beyond 20 million each. This is not of course to say that the importance of USA intervention was not paramount in ending the war and in shaping contemporary Europe. But USA public opinion tends to forget that they have been successful only because Russia, China, UK, etc... had fought for an extent and in conditions that USA troops never experienced. In other words: in a lot of USA media I read stories about the WWII in which it seems that it was the USA to come and free Europe from Nazis and Fascists on its own.
2. An ideological bias onto the so called "communism/socialism": USA public opinion had and still has (even though to a lesser extent) a very shallow understanding of what the socialist economical and political theories are. "Socialism" is used in many of the threads on this very forum as a pejorative word, for example, when not totally out-of context (in a recent thread someody said that Barak Obama is a socialist, just to give an example...). McCarthyism is probably the apotheosis of such medieval attitude towards diversity of views (in Europe we had our fair share with the crusades and the inquisition, btw). While USA public opinion was chasing witches, in Europe - even in those countries that have been always and tightly in the western geopolitical hemisphere - socialism was playing an important role in shaping the public opinion, and the communist parties in various European countries massively contributed to create welfare and social systems that are far better than USA ones (think to health care and education, for example). Again: this is not to say that CCCP was an equally good system than the western democracies, but it is to say that USA public opinion - having an ideological preclusion towards socialism - did not develop analytical tools precise enough to really understand the world and above all the world' reactions to USA global approach. [So that 9/11 got USA people by surprise, or that they got astonished Iraqi population did not welcome USA troops as saviours in Baghdad, etc...]
3. The neocon rhetoric about the "special mission of USA" in the world, with particular emphasis on the "world police" role. This is something that really disconnected USA from the rest of the planet as this role is a purely self-generated illusion by the USA ruling class. Of course - with the fall of CCCP - USA had basically no limits to exercise unilaterally their military and economic power, but this does not mean that people of the planet saw this flexing of muscles as "the police coming to rescue us", hence the recent surge of anti-USA public discourse world-wide.
There are probably many more elements, and somebody who spent time researching on this could probably articulate the previous points to a much deeper level... my point is simply to say that I am not astonished at this point in time many USA people are surprised by the rest of the world being critical of the past 60 years of USA politics... The fact is that that criticism has always been there, but USA public opinion refused to see it for what it was, and labelled it as "propaganda", "misinformation", "socialist lies" and alike.
Finally, I would like to stress that each country has its own "cradle of ideology" according to which that country is the best ever because X, Y and Z... USA simply happens to be the country - at this moment in history - with the most power, and therefore it is normal that the spotlight of public discourse is often on it.
USA has a lot of "right" things in it. Just to mention one: the last presidential election process has been a master class in applied democracy to the world, for example.
But until USA public opinion will not at least try to abandon the lenses of ideology to watch to USA, people from that country will be doomed to have a lot of unpleasant surprises when talking with people from the rest of the world.