A masterly look at the value and limitations of intelligence in the conduct of war from the premier military historian of our time, John Keegan.

Intelligence gathering is an immensely complicated and vulnerable endeavor. And
it often fails. Until the invention of the telegraph and radio, information often
traveled no faster than a horse could ride, yet intelligence helped defeat Napoleon.
In the twentieth century, photo analysts didn’t recognize Germany’s V-2 rockets for
what they were; on the other hand, intelligence helped lead to victory over the Japanese
at Midway. In Intelligence in War, John Keegan illustrates that only when paired
with force has military intelligence been an effective tool, as it may one day be
in besting al-Qaeda.