New York (CNN) -- The defendant's testimony in a stilled Manhattan courtroom Wednesday took a federal jury half a world and many years away, to a mountain cave in the desolation of Afghanistan, to the hours after the September 11, 2001, terror attacks.
In that mountain cave, defendant Sulaiman Abu Ghaith testified, sat the man who had summoned him, his future father-in law: Osama bin Laden.
Bin Laden invited him to sit, Abu Ghaith said, and then asked if he'd heard what happened.
"We are the ones who did it," Abu Ghaith, speaking through an Arabic interpreter, quoted bin Laden as saying. Bin Laden then asked for his opinion of what to expect, Abu Ghaith said.
"America will not rest until it accomplishes two things," Abu Ghaith testified he told bin Laden. "To kill you, and to destroy the Taliban."
"You're being too pessimistic," bin Laden responded.
Abu Ghaith's testimony came on the ninth day of his trial on federal charges that he aided terrorists relating to the 9/11 attacks and conspired to kill U.S. nationals. He has pleaded not guilty to charges that could send him to prison for life if he is convicted.
As he testified Wednesday, several survivors of the attacks and family members of victims sat in the courtroom just blocks away from the World Trade Center and ground zero.
Prosecutors in the terror trial contend Abu Ghaith was an al Qaeda propagandist, with a crucial role in recruiting and inciting the organization's members. Prosecutors have played videos for the jury of Abu Ghaith seated at bin Laden's side, giving speeches filled with fiery rhetoric and issuing calls to "terrorize the infidels."
The defendant said he initially met bin Laden in June of 2001, when he traveled to Afghanistan on "a mission that you may call humanitarian," because of his curiosity about the Islamist Taliban government, and because he thought his skills as an educator and religious scholar could be of use there. In his native Kuwait, Abu Ghaith spent a decade working for the Ministry of Education, and was a licensed imam with a reputation in the Gulf region, he said on the stand.
Shortly after his arrival in the country, Abu Ghaith said, bin Laden summoned him for the first of several meetings. Bin Laden invited him to speak at training camps, saying the men there were exposed to "weapons, roughness, and a hard life," but needed spiritual focus and a lesson in mercy, testified Abu Ghaith. At the camps, he heard talk there was a big al Qaeda operation in the works, he said, but he denied knowing the specifics of the 2001 attack ahead of time.
The first of the video recordings was made at the September 11 meeting, after bin Laden asked for a reluctant Abu Ghaith's help to send a worldwide message, Abu Ghaith testified. He relented only after bin Laden promised to give him "bullet points," and that he'd speak on religious matters only.
"The storm of airplanes will not abate," Abu Ghaith said on one of the recordings, a phrase he testified Wednesday was among the notes bin Laden gave him for the speech.
He maintained in court that his use of "we" and "us" in the videos referred to Muslims and not to al Qaeda, and that he was never a member of the organization.
Abu Ghaith was not asked on the stand about his subsequent marriage to one of bin Laden's daughters.
Abu Ghaith was captured last year after years of being among a group of alleged al Qaeda operatives sheltered in Iran. He was arrested in Turkey and deported to Kuwait via Jordan, which helped U.S. agents capture him.
Testimony continues Thursday, with two remaining defense witnesses. Closing arguments in the case are expected Monday.