When retreat is the decent thing to do

THERE is much to admire about those who fight against impossible odds. Horatius held a bridge over troubled water long enough to prevent the fall of Rome, Leonidas killed thousands of rather incongruously named Immortals and uneducated debt collector Rocky Balboa took world boxing champion Apollo Creed all the way, controversially losing on a split decision.

But there is a fine line between being a plucky hero and a misguided fool. In March 1918, the German commander Ludendorff launched the so-called Spring Offensive to land a knockout blow on the Allied forces. Victory was as likely as the Dalai Lama ru...