There was a long and very amusing article in the New Yorker a couple of months ago about Kaplan's SAT testing prep service. One of the plums of this article consisted in the revelation that they came up with SAT's in order to keep Jews out of the elite American universities. Didn't work of course, but it sheds some light on our own flavor of anti-semitism. Remember too that a lot of Hitler's eugenic practics were born in the good old USA.
In fact anti-semitism was pretty rife in the U.S. until the sixties.
You must also remember that from the point of view of the former USSR and eastern europe, jews enjoyed two advantages after the second world war compared to the rest of the population: 1) many of them that had relatives abroad and received constant aid in the form of goods or money, which they could barter or profit from in their own country. 2) they were pretty much the only ones who could get out.
Joanna