Up until the recent Supreme Court decision there was already oversight. Al Awlaqi was deemed to be an imminent threat and his killing was authorized by the National Security Council which would include 10-20 other individuals with access to superior knowledge of Al Awlaqi’s actions and includes the Chairman of the Joint Chiefs of Staff, the Director of National Intelligence, and the Homeland Security advisor. All people tasked with positively identifying imminent national security threats. The country he was seeking refuge in had even ordered him to be captured dead or alive. And if you’re questioning his involvement in al-Qaeda, he appeared in a video bearing al-Qaeda’s emblem praising the two prior mentioned terrorists and called them students of his.