I think the anti-americanism stems in part from the american things that have exported well, eg. McDonald's, coke, MTV. At the end of the day, if the american things people come into contact with on a day to day business are exploitative multi-nationals, greasy food, bush, gangsta rap, jackass etc, they're not going to have a great opinion of american culture etc. Whether these things would be a true representation of American culture is another question and not one I'm going to answer. All I'll say is the Americans I've met have been great but I met most of them in Europe. I assume that like anywhere else its got its share of bad people and good people. It's a big enough and diverse enough country that generalisations would be pretty useless I would have thought.

On the evil empire thing, Britain did do some pretty horrendous stuff, but I tend to the opinion that people in general can be quite nasty given the oportunity. Eg. a lot of tribes in Africa were only too happy to hand their enemies over to slavers. Doesn't make the slave trade any better mind, just proves that it wasn't just the British or the whites or the christians who behaved horribly. Empires tend to be built on war and a sense of superiority, neither of which are very good for the people being conquered. Having said that there must have been technological benefits and probably political, legal etc ones as well.