One perspective...

The following excerpt was taken from an article in Slate about an obscure correlation between presidential popularity and the strength of the dollar (both of which, at the moment, are quite weak):

"The dollar today may buy fewer BMWs and Prada shoes than it did in 2002,
but it buys about the same amount of Chinese-made microwaves, T-shirts, and
toys. And yes, Americans who suddenly find travel to Europe prohibitively
expensive might be expected to come home enraged. But most of these
travelers already hated Bush. An August 2004 poll showed that voters with passports preferred John Kerry to Bush by a whopping 23-point margin."

This is another illustration of something that I have noticed for quite a while, and since living in Europe, I have found even more striking: the people more likely to travel abroad are the ones who are the most dissatisfied with America-- be it politics, culture or whatever. You will very rarely find your stereotypical American living in Europe, for any amount of time. Some of them might do a little travelling, but they are still more likely to stay at home. Which is one reason why it is so sad that they are the American stereotype. But, as with all stereotypes, they are the ones that stick out and, hence, are the one that are noticed as opposed to their quiet, respectful, culturally oriented counterparts. All of the Americans that I have met, who are living in Europe, lean strongly to the left and are just as appalled at the state of American politics and foreign policy as the majority of Europe.

In my opinion, this can all be traced to the fact that the people who choose to live abroad are more open to foreign cultures and people, and are not impressed with themselves in the world as American citizens, but find more value in being citizens of the world. Which leads to Europeans saying (as one of my colleagues has complained) that they never get any real Americans, just the ones who do not act like how a lot of Europeans think that Americans should act.