The limits of intelligence

Christopher Andrew notes that, thanks to ULTRA and Bletchley Park, Winston Churchill was "best-informed war leader in British history."

Despite this, the first two years of his tenure as PM saw an unending string of defeats. Greece, Crete, North Africa, Malaya, Singapore, Burma. Time and again superior intelligence could not overcome British deficiencies in numbers, doctrine, equipment, and leadership.

For good reason Sir John Keegan wrote

It has become part of the conventional wisdom that intelligence is the necessary key to success in military operations. A wise opinion would be that intelligence, while necessary, is not a sufficient means to victory. Decision in war is always the result of a fight, and in combat willpower always counts for more than foreknowledge.