Fifteen years since the invasion of Iraq, we ask retired US Brig Gen Mark Kimmitt about war crimes and the war's legacy.

Fifteen years after the US-led invasion of Iraq, the consequences of the subsequent war continue to be debated. According to the UN refugee agency, more than four million people have been displaced. There is no widely accepted figure for civilian deaths, but estimates run from the hundreds of thousands into the millions.

"Would we like a do-over, of course we would," says Mark Kimmitt, retired US Brigadier General who served as deputy director of operations and chief military spokesman in Iraq from 2003 to 2004.

While Kimmitt accepts the US "did get some things wrong" in Iraq, he says his country's military has nothing to apologise for.

Actions taken by the US at the beginning of the war continue to have reverberating consequences, including allegations that US detention centres such as Camp Bucca became breeding grounds for armed groups in Iraq, and helped to lay the groundwork for the formation of the Islamic State of Iraq and the Levant (ISIL, also known as ISIS).

"I was worried at the time that the mass incarceration of what the troops on the ground believed to be security threats would come back to haunt us," says Kimmitt. "I told that to my colleagues and I told that to my superiors." While he agrees the Iraq War may have inspired violent groups, Kimmitt insists ISIL was not created in Iraq.

Kimmitt served in Iraq at a time of alleged massacres committed by US soldiers. When asked about dozens of unarmed civilians being killed in places like Fallujah, Haditha, Mahmoudiya and Balad, Kimmitt refuted any claim that civilians were intentionally killed by American soldiers.

"I am not suggesting for a moment that war doesn't sometimes kill innocent civilians. That's the price of war," he said. "As a soldier, what you do is try to minimise it at all costs. But anybody that believes that collateral damage doesn't happen in war is living in a fool's paradise."

In this week's UpFront special, we challenge former US Brigadier General Mark Kimmitt on the consequences and lessons learned after 15 years of war in Iraq.

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Source: Al Jazeera News