Seeking war power authority for three years, President Barack Obama is setting up the prospect that his successor will become the third American president in a row overseeing U.S. military forces grappling with turmoil in the Middle East. Passing on an active military mission in the region would be an unexpected and unwanted legacy for Obama, a president who once appeared poised to fulfill his campaign pledge to end U.S.-led conflicts in the region. […] The president has long said the campaign against the Islamic State militants would be lengthy, suggesting it could extend beyond his presidency. But his authorization...
