DENVER - A decade of time has passed since the start of the U.S.-led invasion of Iraq. It resulted in the removal of Iraq's dictator Saddam Hussein and his regime.

In the years since, the Iraqi government has struggled to quell sectarian violence. On the 10 year anniversary of the start of the war a string of bombings in Iraq resulted in the deaths of 65 people.

"The problems of Iraq have proven extremely complex, and to this day when we see more of the Sunni extremist violence against the Shia we realize there is much to be done by Iraqis, not American troops," said Christopher Hill, former U.S. Ambassador to Iraq and the Dean of the School of International Studies at the University of Denver.

Hill says that while Iraq continues to struggle with sectarian and ethnic rivalries, the country has benefited from the removal of Saddam Hussein.

"On the positive side of the ledger we are rid of Saddam Hussein who was definitely a menace. He had invaded his own neighbor. It was a good day to get rid of Saddam Hussein," Hill said.

Hill says the mistake that was made was in believing that the removal of Saddam Hussein would solve the problem of the region.

"I think those hopes were really never there and I think one of the worst legacies of Iraq are the people who claim that somehow by getting rid of the dictator, Saddam Hussein that this would be transformational in the rest of the region," Hill said.

The U.S. troop involvement in Iraq ended in 2011. The freedom the Iraqi people now enjoy was paid for with the sacrifice of American servicemen and women.

"For me, I can say it is a time of reflection. We lost some 4,600 of our citizens in that country," Hill said.

How history will remember the events of March 20, 2003 won't be known for some time. It will be determined by the future of the fragile Iraqi government and its future relations with the U.S. government.

Hill says regardless of the Iraq's future, he hopes this country will remember the lesson of the last ten years.

"I hope we've learned that you really need to understand these situations a lot better when you commit your young men and women to go into this," Hill said.