I believe that's a good reason to talk bad about USA
Do you realise that by "USA" you might mean "certain people of power within USA"?
I haven't met many Americans. On backpacker I met was a complete bull-[nocando] artist. On the other hand, my aunt's family is American and they're great (and not just because they are family). I've made American friends on this and other forums and find little difference between them and local friends. I've also met a lot of not-so-nice Americans on the 'Net and I ignore them like I would someone here.
America is a different culture. It is so frequently exposed that we all feel informed enough to make opinions. Of course, we only see the exciting bits...