There's a fascinating comment thread after this post by Iain Dale, fascinating because it shows how widespread anti-Americanism now is. The post is about an incident on a tube:
I have my own take on this. I make a point, as my friends will attest, of wearing a pair of stars and srtripes cufflinks. It might be slightly pathetic, but I want to demonstrate my solidarity with the nation leading the fight against barbarism.
Understandably, when strangers see but don't hear me, some jump to the conclusion that I am American. And it's instructive to see how some people behave when they see the cuffs.
On countless occasions I have been sneered at, sworn at and, twice, spat at. I would say - my memory is impressionistic on this - that by far the most common insult is a muttered "F*c*ing American". And I cannot recall such behaviour from anyone who looked older than 40ish.
Not being American, for me this is simply useful in seeing how common such prejudice is. Of course, just because it is only the under 40s who are vocal, it does not follow that others do not share their views.
It's not that usual to hear people give voice to their anti-semitic or anti-black bigotry. But in my experience, there is one prejudice which is now entirely acceptable: anti-Americanism.