Anti-Zionism != Anti-Semitism
I have several good Jewish friends who are not Zionists - they live in the UK not Israel - at least one of whom dispairs about the grief he suffers travelling the world as a non-zionist Jew due to "irresponsible Israeli beligerence".
The various Middle-East threads may have posts critical of Israeli policy today and the political process in the late 19th / early 20th C. which lead to the creation of the current incarnation of Israel.
While there may have been occaisional hot-headed posts the various threads were mainly looking at the aspects of the historical background which are still percieved as injustices or betrayals by some fraction of the people who live in that part of the world, and had they been allowed to continue might have speculated as to what could be done to right these (real or merely perceived) wrongs.
This is by no means anti-semitic, even were we to conclude that the Zionist POLITICAL movement was a barrier to peace.
 dinner/houseguest/wedding party/aerobatic flight level, not just work aquintance, and far, far closer than any Muslim aquaintance.