Osama bin Laden's son-in-law told spellbound spectators in a New York court today that even though he appeared with his infamous kin in videos shortly after the 9/11 attacks, he didn't know the attack was coming beforehand and two never discussed terrorism.

Suleiman Abu Ghaith, who officials call the highest-level al Qaeda member to face trial in the U.S., was testifying in his own defense just a mile or so from where the World Trade Center buildings used to stand. Sitting in a suit provided by the court and no tie, Ghaith tried to convince a jury that he spoke on al Qaeda's behalf so many years ago unwillingly and was actually trying to curtail bloodshed.

Ghaith told the court through a translator that he had seen the events of 9/11 unfold on television in Kabul before being summoned by bin Laden to the Afghan caves where al Qaeda leaders were holed up.

"We were the ones that did it," bin Laden said, according to Ghaith. Then Ghaith said bin Laden asked him to "deliver a message to the world."

Ghaith said he didn't want to do it and asked bin Laden to "kindly spare me this mission." But bin Laden insisted and, Ghaith claims, provided bullet points justifying the attacks. In a video released shortly after the attacks, which has been entered into evidence in this trial, Ghaith sits cross-legged next to bin Laden as the al Qaeda founder praised the American deaths. Bin Laden wouldn't officially take responsibility for the attack until years later.

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In one rather extraordinary moment Ghaith appeared to portray himself as a mediator between bin Laden and the U.S. As fighting raged in Kabul, Ghaith said he made several more videos in which he warned of a new "storm of airplanes," an apparent reference to the 9/11 attacks. However, Ghaith said he was hoping the videos would curb "the amount of attack" on the defenseless people of Afghanistan.

"I wanted to proclaim the message that Muslims had to defend themselves," he said.

During the course of his testimony Ghaith denied recruiting for al Qaeda as alleged, saying "only Sheikh Osama could do that." He also denied knowledge of Richard Reid's shoe bomb plot in December 2001 and said he never discussed terrorism with Khalid Sheikh Mohammed, the alleged mastermind of 9/11.

Ghaith has pleaded not guilty to the charge of conspiracy to kill Americans and support a terrorist organization. He has been described by American officials, including Chairman of the House Homeland Security Committee Michael McFaul (R-Texas), as a former member of al Qaeda's "inner circle."