In a letter to the Congress on Sunday, Obama said: "On August 14, 2014, I authorized the U.S. Armed Forces to conduct targeted air strikes to support operations by Iraqi forces to recapture the Mosul Dam. These military operations will be limited in their scope and duration as necessary to support the Iraqi forces in their efforts to retake and establish control of this critical infrastructure site, as part of their ongoing campaign against the terrorist group the Islamic State of Iraq and the Levant (ISIL)."
He said the failure of the Mosul Dam could threaten the lives of large numbers of civilians, endanger U.S. personnel and facilities, including the U.S. Embassy in Baghdad, and prevent the Iraqi government from providing critical services to the Iraqi populace."
"Pursuant to this authorization, on the evening of August 15, 2014, U.S. military forces commenced targeted airstrike operations in Iraq," Obama said.
"I have directed these actions, which are in the national security and foreign policy interests of the United States, pursuant to my constitutional authority to conduct U.S. foreign relations and as Commander in Chief and Chief Executive. These actions are being undertaken in coordination with the Iraqi government," he said.
Obama said: "I am providing this report as part of my efforts to keep the Congress fully informed, consistent with the War Powers Resolution (Public Law 93-148). I appreciate the support of the Congress in this action."