Well, y’know, some people watch American Idol, and some of us sit at our computers and think of new things to blame America for. 
Getting past the kidding, though:
I have, for all of my life, assumed America was the Good Guys in the world. My worldview in this regard was formed before Vietnam took center stage in our foreign policy in the mid-1960s, in a time when we were the country that won WWII (I’m talking about my perceptions as a kid, here, so no need to talk about Russia’s role) and WWI before that, and was now protecting the world from the evils of totalitarian Communism.
And on account of that legacy, I expect America to live up to that sort of ideal, or at least give it its best shot. I demand of my country that it not be just strong, but to use its strength on the side of what is right and good.
That view of America has taken some hits over the years, of course. It’s had to survive Vietnam, Nixon-Kissinger realpolitik, our support of numerous anticommunist tinhorn dictators like Marcos, Pinochet, Somoza, Saddam, and the Shah, and that flock of neocon surrogate wars during the 1980s: El Salvador, Nicaragua, Angola. I had to believe there was a better way of fighting Communism than by supporting ‘authoritarian’ (you’re welcome, Jeane Kirkpatrick) thugs around the world: we got democracy; El Salvador got Roberto D’Aubuisson.
But I didn’t think America was evil; America was good, but for often difficult to understand reasons, it was doing wrong. What do you do about it? You call a spade a spade: you say what’s wrong and what’s right, and you expect your country to get back on the right track.
And there were some positive developments along the way. Jimmy Carter, for all his other failings, insisted that we look at how all countries, not just Communist ones, were falling short on human rights, and take that into account in our foreign policy. The Helsinki Accords, excoriated by conservatives at the time, gave us some leverage to demand of the USSR that some degree of human rights be accorded to its Warsaw Pact vassals. And while Reagan had far too many neocon nutcases running his foreign policy (Richard Perle, Elliott Abrams), Reagan’s heart really was in the right place - he believed in freedom not just as a slogan but as a fundamental human right - and his policies gradually caught up. Along about 1983, he and his team came to the realization that D’Aubuisson was a murderous thug, and lined up behind Duarte instead; when crunch time came in the Phillippines in 1985, he helped nudge Marcos out; in 1987, he and Carter combined to hornswoggle Daniel Ortega into holding elections - and honoring them, when they didn’t go his way; and, most significantly, when he finally had a Soviet opposite number in Gorbachev who actually believed Communism should benefit the people living under it, he had the right combination of willingness to take diplomatic chances while maintaining public pressure to hasten the moment when the Wall would come down - a moment that most of us who grew up during the Cold War weren’t sure we’d live to see.
And then of course Clinton, without a Cold War foe to reckon with, gradually found his footing, and put the United States on the right side of things in Bosnia and Kosovo.
So I believe America can do great things in the world when it is good as well as strong. And I believe that when America is doing evil, and we call it by its name, America will eventually respond, and find its way back to the light.
So when America turns into a swaggering bully in the world, invading other countries without knowing WTF it’s doing and what forces it’s unleashing, let alone having a plan to deal with them, I will call it evil, and demand that America stop doing evil and do good. I will do the same when we imprison people for years when we have zero evidence that they’ve done anything hostile to us, and when we torture people, and send them off to other countries to be tortured. And when we bomb the shit out of civilians along with insurgents - insurgents who would have had little support for their insurgency if we simply weren’t there. And when our government spies on its own people without any legal authority or oversight. I want the country I’ve lived in all my life to deserve to wear the white hat again, and I want leaders who believe in the goodness of America in a way that causes them in turn to demand the best out of America - rather than believing that whatever America does is automatically good because it’s America that’s doing it.
So if I’m critical of America, it’s because I’m a fucking idealist, and for some reason, despite everything I’ve seen in my life where it’s fallen short, America is still one of the things I’m an idealist about. It’s totally irrational, and it makes no sense, but there it is.