Ron Paul suggested the Jews were behind the 1993 World Trade Center bombings.
The New Republic reported, via RedState:
One of the more insane claims in Ron Paul’s newsletters was that the Israelis were behind the WTC bombings in 1993:
Whether [the 1993 World Trade Center bombing] was a setup by the Israeli Mossad, as a Jewish friend of mine suspects, or was truly a retaliation by the Islamic fundamentalists, matters little.