I came here to rolly eyes at exactly the same line.

In the 2004 Osama bin Laden video, he vividly and explicitly describes where he got his primary motivation for the attack. This was his vengeance for the carnage he saw in the media coverage of the Israeli siege of Beirut, in the 1982 Lebanon War, where Israel was helped by the United States. Other motivations were published in the 2002 Letter to the American People, in which he said that al-Qaeda’s motives for the attacks included American support for attacking Muslims in Somalia, supporting Russian atrocities against Muslims in Chechnya, supporting the Indian oppression against Muslims in Kashmir, condoning the 1982 massacres in Lebanon, the presence of US troops in Saudi Arabia, US support of Israel, and sanctions against Iraq. Bin Laden and Ayman al-Zawahiri asserted that Israeli repression of Palestinians during the Second Intifada was the immediate cause that forced Al-Qaeda to launch the September 11 attacks.