Pfc. Naser Abdo, 21, is being held without bond. He has been charged with possessing an illegal firearm, two days after he was arrested. Authorities say they found weapons stashed in a motel room where he was staying about 3 miles from Fort Hood's main gate.
In court, Abdo refused to stand up when asked to in court. Then as he left the room later, he yelled, "Nidal Hasan Fort Hood 2009."
His words in court were a sharp contrast to an essay he wrote last year as the first anniversary of the Fort Hood shootings approached. In the essay, obtained by The Associated Press, Abdo said the attacks ran against his beliefs and were "an act of aggression by a man and not by Islam."
Prosecutors say he planned to build two time bombs and detonate them near a restaurant frequented by soldiers.
Abdo had been granted conscientious objector status because his Muslim beliefs.
The Associated Press contributed to this story.