The attack was never carried out, and six men, all foreign-born Muslims in their 20s who lived for several years in southern New Jersey, were arrested in May 2007.
One of the men, Agron Abdullahu, a supermarket baker, pleaded guilty last year to providing weapons to some of the others and is now serving a 20-month prison sentence.
In a videotape shot using a camera mounted in Omar's car, Shnewer remarks that Fort Dix is much more easily accessible than military bases in the Middle East, which are miles from civilian streets - something he attributes to the arrogance of the American military.
"Their noses are up," he says. "'We are America and no one can hit us.' And we are going to make them think differently, God willing."
The videotape follows Shnewer and Omar, who is driving, as they get lost on their way to the base. When they finally get there, they sound discouraged as they appear to find no suitable targets.
Then, they pull over to the side of the road and Shnewer looks out the car window and says, "This is it."
On the witness stand, Omar said through an interpreter that at that moment, a group of Army vehicles passed them going in the opposite direction and made a turn.
Later in the conversation, Shnewer discusses attempting to get a mortar or other heavy artillery, and describes to Omar how nail bombs could be left on the road and detonated by remote control while other attackers would spray the vehicles with machine-gun fire.
Defense lawyers contend Omar was the mastermind of any plot that existed and that he goaded the defendants and exploited their anti-American views.
In one tape segment, Shnewer speaks of Omar as "the brains of the operation."
In other conversations played in court Wedneday, Shnewer suggests the men train in the Pocono mountains during the winter so they won't raise suspicion. He also says he could buy a machine gun for about $400.
The government's investigation into the alleged plot began with a tip from a clerk at a Circuit City electronics store in Mount Laurel.
He called police in January 2006 after he was troubled by a video that customers asked him to convert to a DVD. Authorities say the home-shot footage featured men at a firing range shouting "Allah Akbar," Arabic for "God is Great."
Shnewer and the other four defendants - Serdar Tatar and the brothers Dritan, Eljvir and Shain Duka - face charges of attempted murder and conspiracy to murder uniformed military personnel; four of them are also charged with weapons offenses.
All have been in federal custody since they were arrested and face life in prison if they are convicted.