though he be sheltered behind a high rampart and a deep ditch. All we
need do is attack some other place that he will be obliged to relieve.
[Tu Mu says: "If the enemy is the invading party, we can cut his line
of communications and occupy the roads by which he will have to return;
if we are the invaders, we may direct our attack against the sovereign
himself." It is clear that Sun TzÅ, unlike certain generals in the late
Boer war, was no believer in frontal attacks.]