An Army captain sued President Barack Obama on Wednesday, alleging that he doesnt have the proper congressional authority to wage war against Islamic State militants in Iraq and Syria. Capt. Nathan Michael Smith filed the suit in U.S. District Court in Washington as the president is deploying more special operations forces to the region and a day after a Navy SEAL was killed in combat in Iraq, the third since a U.S.-led coalition launched its campaign against the Islamic State in the summer of 2014.