Resalat: Today Brigadier General Yahya Rahim-Safavi, commander of the Iranian revolutionary guards, said concerning the September 11 attacks, "This plot was not masterminded by al-Qaeda. It was masterminded by Mossad and carried out by al-Qaeda.". So with confessions with like this from al-Qaeda members recently it's getting harder for even the most irrational people to live in denial. So they blame the usual conspiracy theory favourites. This is the "big lie" theory in practice from the Iranian leaders. Remember the quote from Hitler:

"...the broad masses of a nation are always more easily corrupted in the deeper stata of their emotional nature than consciously or voluntarily, and thus in the primitive simplicity of their minds they more readily fall victims to the big lie than the small lie, since they themselves often tell small lies in little matters but would be ashamed to resort to large-scale falsehoods." -- Hitler, "Mein Kampf"

Resalat is one of the hardliner newspapers. It is difficult to decide sometimes whether the hardliners really believe what they are saying or whether they are just attempting to distract from the government's failings, or just self-denial that Muslims could have been responsible. Westerners can't believe it, but the distraction strategy has worked wonders for 23 years here. Iranians have always been big belivers in conspiracy theories. Conspiracy theories enable people to avoid self-criticism and blame others for all their problems. If a large part of the population believes in conspiracy theories, it's quite easy for demagogues to take over, as has happened in many countries.

I'm not sure to what extent Rahim-Safavi's views are held in the general population. But I recently read the 4000 Jews didn't go to work in the WTC on 9/11 theory in an "moderate" English-language daily, "Iran News". I haven't seen the Gallup poll figures for Iran on the September 11 question, but I remember reading the methodology of the poll was suspect.