In the ten years since the September 11 terrorist attacks on America, conspiracy theories surrounding the attacks have become an entrenched propaganda industry. These assaults on memory and history attempt to place blame for the attacks on sources other than Al Qaeda, such as the U.S. government. Prominent among such 9/11 conspiracy theories are those that make the anti-Semitic claim that Jews—whether Israeli, American, or both-- were involved in planning and executing the attacks. This anti-Semitic faction is only a part of the so-called "9/11 truth movement," yet it is vocal and pervasive, particularly on the Internet. While its origins began within hours of the attacks themselves, a new chorus of voices—who claim not to be anti-Jewish but simply anti-Zionist—have more recently emerged to become the most popular promoters of these ideas.
The goal for these anti-Semitic "truthers" is to convince the public that the actual terrorists never could have masterminded or conducted the 9/11 attacks. Instead, they claim, American and/or Israeli Jews were the only ones who had the "motive, means, and opportunity" to carry them out. Blaming Jews for manipulating world events for their own benefit is not new–it is at the very root of ideological anti-Semitism. Anti-Semitic 9/11 conspiracy theories are merely a recent manifestation of age-old allegations that a Jewish cabal plots deceitful, sinister actions in order to gain or maintain power.
Anticipating criticism, a number of these anti-Semitic conspiracists now try to immunize themselves against charges of anti-Semitism by making disclaimers up front about not being anti-Semitic. Their own works and record, however, blatantly contradict their innocuous self-characterizations.
The most prominent promoters of these anti-Semitic conspiracy theories today tend less often to be white supremacists and right-wing anti-Semites. Rather they are more commonly members of a group of anti-Israel conspiracists who see the 9/11 attacks as one of a series of "false flag" operations that Israel has carried out to manufacture a war against its Muslim enemies (the term "false flag" operations refers to acts of sabotage or terror conducted by one perpetrator but designed to appear as if conducted by another, with the goal of setting the victim at odds with the false perpetrator).
Read more at ADL.org.