In absence of Osama (who I believe is dead or retired in some exotic place long ago), the "second in command" of the most feared international terrorist network, Ayman Al Zawahiri (actually the boss right now) has accused Iran of spreading the rumor that Israel (sic) was behind the 9/11 attacks against New York and the Pentagon.
More specifically, he blames Hizbullah, the Lebanese Shia Islamist party, militia and state-within-the-state, for being the first one to spread such rumors, "obviously" intended to discredit Sunni Islamist "heroism".
Problem, Mr. Al Zawahiri, is that the people like me that began to have serious doubts in the very aftermath of the massacre, as quickly supressed news of the supposed Al Qaeda cells being actually anti-Taliban (who do you believe: the CIA or the most professional German BND?) and of M. Atta being alive (a story his father apparently still sustains), were broadcasted. We also know who was the boss of Osama for so many years: the CIA, and we know that Al Qaeda took months to assimilate the issue and claim authorship.
In brief: there have been many doubts since 9/12. Maybe Hizbullah was among the first ones casting doubt in the Middle East, but certainly the subject was very controversial here in the West much earlier.
Mr. Al Zawahiri, you forget something important: the World is not just the Muslim world. Allah, may be great, but Reality is much greater.