President Obama formally notified Congress on Monday that he authorized air strikes to free the Iraqi city of Amerli, which had been under a two-month ISIS siege. Iraqi forces with Shia militias were able to break through the ISIS blockade on Sunday with the help of U.S. air strikes. The U.S. also used the strikes to provide humanitarian aid. “This operation is consistent with the military missions we have outlined to date in Iraq – to protect U.S. personnel and facilities and to address the humanitarian situation on the ground," said National Security Council spokeswoman Caitlin Hayden in a statement. Under the the War Powers Resolution, Obama has to notify Congress of authorizing such a strike.