Conservative estimates pin the number of Iraqi civilian causalities at 100,000.
As the United States and its allies warred with their enemies, millions of innocent people got caught in the middle. One of them was Ezadeen Naji, a teenager living in Baghdad when the invasion began.
He's now 24 and a student at Pima Community College, but he can vividly recount the tumultuous path that brought him to the U.S.
Fear consumed Naji at the outset of the war, keeping him penned up at home. After a few days, he stopped worrying so much because he knew anxieties wouldn't shield him from walking into somebody's cross hairs.
Within a week, he and his friends were playing soccer in the streets as rockets cruised overhead and buildings collapsed around them. On days when the violence was particularly bad, he spent hours at his mosque, reading the Quran and praying for the cataclysm enveloping him to come to a halt.
"Some good things came out of the war. But overall … it was destruction. That's what I think of the anniversary," he said. "Destruction."
At night, Naji could lie on a rooftop and see "all the stars in the sky" because the city's lights and power stations weren't functional for months, he said. Water was scarce, so his family had to dig their own wells.
Several of his relatives were killed, sectarian crime increased dramatically, heaps of garbage cluttered the streets and the nation's overall condition deteriorated beyond anything he endured under Saddam Hussein, he said.
Naji and his family left Iraq in 2006. They spent two years in Syria before coming to Tucson in 2008 as refugees.
He's studying electrical engineering at PCC and plans to transfer to the University of Arizona next fall. "When I came here, I knew it wasn't the American people who wanted to hurt us. The people were very nice and welcoming," he said. "The war was started by politicians."
"Some good things came out of the war. But overall … it was destruction. That's what I think of the anniversary. Destruction."
Ezadeen Naji, Pima Community College student