http://en.wikipedia.org/wiki/New_antisemitism
From a wikipedia article detailing why it would be anti-semitic to critisize Jessica Seinfeld....
Bernard Lewis, Cleveland E. Dodge Professor Emeritus of Near Eastern Studies at Princeton University, argues that the new antisemitism represents the third or "ideological" wave of antisemitism, the first two waves being religious antisemitism and racial antisemitism, respectively. [40]
Lewis defines antisemitism as a special case of prejudice, hatred, or persecution directed against people who are in some way different from the rest. According to Lewis, antisemitism is marked by two distinct features: Jews are judged according to a standard different from that applied to others, and they are accused of "cosmic evil." Thus, "it is perfectly possible to hate and even to persecute Jews without necessarily being anti-Semitic" unless this hatred or persecution displays one of the two features specific to antisemitism. [40]
He writes that what he calls the first wave of antisemitism arose with the advent of Christianity because of the Jews' rejection of Jesus as Messiah. The second wave, racial anti-Semitism, emerged in Spain when large numbers of Jews were forcibly converted, and doubts about the sincerity of the converts led to ideas about the importance of "la limpieza de sangre", purity of blood. [41]
Lewis associates the third wave with the Arabs, and writes that it arose only in part because of the establishment of the State of Israel. Until the 19th century, Muslims had regarded Jews with what Lewis calls "amused, tolerant superiority" — they were seen as physically weak, cowardly, and unmilitary — and although Jews living in Muslim countries were not treated as equals, they were shown a certain amount of respect. The Western form of anti-Semitism — what Lewis calls "the cosmic, satanic version of Jew hatred" — arrived in the Middle East in several stages, beginning with Christian missionaries in the 19th century, and continued to grow slowly into the 20th century, up to the establishment of the Third Reich. He writes that it increased because of the humiliation of the Israeli military victories of 1948 and 1967. (See 1948 Arab-Israeli War and Six Day War.) [41]
Yehuda Bauer, Professor of Holocaust Studies at the Hebrew University of Jerusalem, writes that there have been three waves of anti-Semitism since 1945 — 1958-60; 1968-1972; and 1987-1992 — and that we are now experiencing the fourth, which he estimates started in 1999 or 2000. [42] Each wave has had different causes, some of them to do with economic downturns, though the common ground has been "an underlying latency of anti-Semitism that waits to explode when aroused by some outside crisis." [43] He describes the fourth wave as an upper-middle class, intellectual phenomenon, "widespread in the media, in universities, and in well-manicured circles.