The senior Al Qaeda leader appeared in a New York Federal Court despite complaints from Republicans who say high threat terrorists should be held at Guantanamo Bay, not in the United States.
The accused terrorist was bearded and wearing a blue prison uniform, his hands cuffed behind his back.
A seven page indictment accuses the alleged Al-Qaeda spokesman of plotting in the September 11th, 2001 terrorist attacks and later threatening the United States.
Prosecutors say the alleged terrorist has cooperated, providing a 22-page statement.
Abu Ghaith was captured late last month heading from Turkey to Jordan and brought to the United States,
angering Republicans who call him a dangerous enemy combatant.
"When it comes to people like this that we want them to go to Gitmo to be held in military custody for interrogation purposes," argued South Carolina Senator Lindsey Graham.
Legal experts, however, say conspiracy is not typically considered a war crime.
"There is a vastly better chance in convicting Abu Ghaith in a civilian court in the Southern District of New York than in a military commission and having that conviction withstand an appeal," says Brookings Institution national security expert Wells Bennett.
Abu Ghaith would be one of the first senior Al-Qaeda leaders tried on American soil.
He is due back in court in early April.
If convicted he could face life in prison.