KILLEEN, Texas (KWTX) - U.S. troops officially pulled out of Iraq on Sept. 30, ending more than two decades of operations in the country.U.S. forces invaded Iraq in March 2003 for Operation Iraqi Freedom, following the attacks on Sept. 11, 2001.

Retired Army veteran John Valentine served in Afghanistan and Iraq.

He said he is glad troops have pulled out but understands they had a job to do."I think we just have to be mentally prepared that there's going to be a time leave and there's a time to go. Psychologically, the soldiers that are in the military right now have to understand that that's their job. They've got to do the best they can with what they're told to do and then they need to do the best they can when it's time to leave," Valentine said.