One of the odder notions to take hold in recent years is that AIPAC specifically, and the so-called "Israel lobby" more generally had absolutely nothing to do with the Iraq War, and that anyone who says otherwise is an anti-semite. As John Judis writes for The New Republic, however, this is just false:
At the time, a Senate staff person with a responsibility for foreign policy told me of AIPAC's lobbying. But I don't have to rely on my memory. AIPAC's lobbying wasn't widely reported because AIPAC didn't want Arab states, whose support the Bush administration was soliciting, to be able to tie Bush's plans to Israel, but it lobbied nonetheless. In September 2002, before Congress had begun considering the administration's proposal authorizing force with Iraq, Rebecca Needler, a spokeswoman for AIPAC, told the Jewish Telegraphic Agency, "If the president asks Congress to support action in Iraq, AIPAC would lobby members of Congress to support him." Then at an AIPAC meeting in New York in January 2003, before the war began, but after Congress had voted to authorize Bush to go to war, Howard Kohr, AIPAC's executive director, boasted of AIPAC's success in lobbying for the war. Reported the New York Sun, "According to Mr. Kohr, AIPAC's successes over the past year also include guaranteeing Israel's annual aid package and 'quietly' lobbying Congress to approve the use of force in Iraq."
And, obviously, other institutions of the hawkish "pro-Israel" establishment -- the Washington Institute for Near East Policy, the Saban Center, JINSA, The New York Sun, The New Republic, etc. -- all advocated strongly in favor of invasion. That's not to say that "the Jews caused the war" (I think Bush, Cheney, Blair, Powell, Rumsfeld, Rice, etc. had a little something to do with it) but it's still true.