He said he learned from comic books as a child that there were oppressors and oppressed people in the world, and in school developed an admiration for Native Americans and civil rights leaders including Malcolm X.
Declaring himself "a very proud Muslim," he blamed sanctions against Iraq for the deaths of thousands of children and said Muslims should defend themselves against foreign invaders.
"This is not extremism," said Mehanna.
Federal prosecutor Aloke Chakravarty told the judge FBI agents said some of Mahenna's statements were false.
"You're a liar!" Mehanna shouted at the prosecutor.
As he was escorted out of the courtroom in handcuffs, Mehanna kissed the air toward family and friends, who clapped and shouted, "We love you, Tarek!"
(Editing By Barbara Goldberg and Mohammad Zargham)