If there’s one thing America’s misadventure in Iraq from 2003 to 2011 taught everyone, it is that things can go terribly wrong when the U.S. intervenes in a foreign environment with deep sectarian divisions, an ineffectual government, armed factions, and the general complexities of the Middle East.

So now, Barack Obama plans to step up U.S. involvement in Iraq with more airstrikes and an effort to strengthen and better organize Iraqi and Kurdish military forces, as well as some Syrian rebels. In his address to the nation Wednesday night, the president laid out a multi-point proposal for action. He also had an opportunity, which he chose not to take, to warn Americans of some of the specific ways his new intervention could go wrong. “Any time we take military action, there are risks involved, especially to the servicemen and women who carry out these missions,” Obama said. But he did not elaborate or explain any of those risks.