The trial began on Tuesday of a Syrian man accused of supplying a component of improvised bombs used in the Iraq war.
Ahmed Alahmedalabdaloklah is accused of making circuit boards used to remotely detonate roadside bombs in Iraq for the 1920 Revolution Brigade.
A prosecutor said he had sympathised with a group that wanted to use violence to drive a wedge between Iraqis and Americans
The trial is being held in Phoenix because authorities said a part for improvised devices was made by a company based in Arizona.
Prosecutor Joseph Kaster told jurors in opening statements that Mr Alahmedalabdaloklah embraced the group's objectives to force American troops out of Iraq.
"He shared (the brigade's) violent objectives," Mr Kaster said.
The case against Mr Alahmedalabdaloklah, 40, arose out of a raid a decade ago at a Baghdad flat where soldiers discovered a large cache of bomb-making materials, although no explosives were found.
Prosecutors claimed Mr Alahmedalabdaloklah's fingerprints were found on several items in the raid.
Authorities said in court records that several witnesses have tied the defendant to the production of IED components, including one person who said Mr Alahmedalabdaloklah, after fleeing Iraq and moving to China, found a factory in China to make the circuit boards.
Mr Alahmedalabdaloklah has pleaded not guilty to charges of conspiracy to use a weapon of mass destruction, conspiracy to destroy US government property with an explosive, possession of a destructive device in furtherance of a violent crime, conspiracy to commit "extraterritorial murder" of a US citizen and providing support to terrorists.
If convicted, he could face up to life in prison.
Defence lawyer Jami Johnson said her client never expressed any sentiments against Americans in 12 years of his emails that were reviewed by investigators. "Twelve years — and not one single anti-American statement," Ms Johnson told jurors.
She said her client, who was taken to Iraq as a refugee when he was a child, operated a legitimate electronics shop in Baghdad and moved to China when security in Iraq fell apart.
Ms Johnson said Mr Alahmedalabdaloklah set up an electronics business in China that sold products in Iraq and elsewhere but never sent any components used in a bomb.
She said her client's fingerprints were found on his photos and documents inside the Baghdad flat, but none of the electronics contained his prints or DNA.
Mr Alahmedalabdaloklah was arrested in May 2011 after flying to Turkey from China. He was jailed for three years in Turkey before being extradited to the US in August 2014.
Prosecutors have said in court papers that 1920 Revolution Brigades claimed responsibility for 230 attacks in Iraq against American soldiers from 2005 to 2010.
The 1920 Revolution Brigade was active against US forces in Sunni-dominated parts of Iraq until it switched sides in 2007 to fight against Al Qaeda. The group derived its name from the 1920 revolution in which Iraqis revolted against a British occupation.
