The U.S.-led coalition originally invaded Iraq in 2003 to topple Saddam Hussein, withdrew in 2011, and returned in 2014 to fight the Islamic State.

From the articleU.S. confirms withdrawal of troops in Iraq, leaving questions about country's security | CBC NewsAlso in Pentagon says it has formally completed withdrawal of US troops from Iraq, ‘Quagmire’ over: Trump hails US exit from Iraq after 12-year ISIS mission, Last US-led coalition forces withdraw from Iraq after 12 years, Trump hails the US military’s exit from Iraq after 12-year mission against Islamic State, Pentagon says US troop withdrawal from Iraq is complete