One of the most undercovered aspects of Obama’s legacy has been how he has waged war, unilaterally expanding the original 2001 Authorization for Use of Military Force (AUMF) against the perpetrators of the September 11 attacks almost beyond recognition. It’s currently being used to legally justify the administration’s war on Isis in about a half dozen countries (that we know of), despite Isis not being in existence at the time AUMF was passed. It’s also being used to authorize action against a host of other groups, though who they are is classified.