One portion of this is simply a group-think phenomenon - an opinion or a set of opinions put on like a uniform in order to validate one's group membership. This happens a great deal on university campuses. And some of it is self-validating as well, as in "all the smart people I admire think this, hence I'll think this, hence I'm smart and admirable."
The sad part is that persons espousing this set of beliefs for this reason simultaneously cast their own self-image as independent-thinking and non-conformist. Largely, one supposes, because all the smart people do so...
Paul Johnson, the British historian, makes a good point about anti-Americanism in the new American Spectator print edition.
I'll post it on this thread but it'll take a while for me to type it out.
"A new factor intervened in the 1990s when the collapse of the Soviet Union, and the demise of international Communism as an active force left the United States as the sole superpower and free enterprise, symbolized by the U.S. as the only ideology. Anti-Americanism, popular among the European left throughout the Cold War, together with its own self-hating version within the U.S., now entered a new and virulent phase powered by a sense of absolute despair. The Left now had no faith, no belief in a Utopian future, no allies to admire, no heroes and no causes to promote. In this negative mood, anti-Americanism, irrational, wholly destructive, violently emotional and protean in that it could easily be made to fit the circumstances of the movement, was the perfect formula to fill the Left’s vacuum of thought." – (Paul Johnson, “Street Fighting Men”, The American Spectator, October 2003)