It’s a foreign-policy humiliation unlike anything our country has endured since the Iran hostage crisis. The likelihood there’s going to be the Taliban overrunning everything and owning the whole country [of Afghanistan] is highly unlikely,” President Biden confidently proclaimed in July. “There’s going to be no circumstance where you see people being lifted off the roof of an embassy.” One month later, the scenario Mr. Biden deemed impossible has become a horrifying reality. In recent days, the world has watched panicked civilians cling to U.S. military aircraft in a desperate attempt to escape the chaos unleashed by Mr. Biden’s reckless...