The president tells us that “a hasty withdrawal would create a vacuum that terrorists, including ISIS and al-Qaeda, would instantly fill, just as happened before September 11.” Really? Is Afghanistan truly a vital national security threat? If so, the president just made the slippery case for an expanded American military presence in Yemen, Libya, Nigeria, Somalia, Syria, Iraq, Saudi Arabia, Chechnya, and, well…Europe. That would be a lot of boots on the ground.