Most aggressors take stupid risks only when they feel they won't be stopped. The world seems to be falling apart. Only lunatics from North Korea or Iran once mumbled about using nuclear weapons against their supposed enemies. Now Vladimir Putin, after gobbling up the Crimea, points to his nuclear arsenal and warns the West not to “mess” with Russia. The Middle East terrorist group the Islamic State keeps beheading its captives and threatening the West. Meanwhile Obama admits to the world that we “don’t have a strategy yet” for dealing with such barbaric terrorists. Not long ago he compared them...