Whilst I was at the bookstore some weeks ago I decided, for some
unaccountable reason, that I wanted to learn more about military
strategy. I cast about to see if I could find something like
Military Strategy for Dummies or
Warfare for the Compleat Idiot, but those titles were
conspicuously lacking. This book doesn’t quite meet that need, but it
goes part of the way and it was an interesting read besides.

Alexander begins by observing that “The rules of war are simple but
seldom followed,” and that attacking a prepared position usually results
in slaughter for the attackers. Instead, “great generals strike
where they are least expected against opposition that is weak and
disorganized.” The remainder of the book is a series of
case studies of great generals and how they won their greatest battles:
How Hannibal Barca won at Cannae and how his nemesis Scipio Africanus
finally defeated him. How Genghis Khan and his generals conquered the
geographically largest empire the world has ever seen. How Napoleon
Bonaparte won his early battles. How Stonewall Jackson used his small
force to neutralize far larger Union forces. How William T. Sherman won
the Civil War by doing in the South what Stonewall Jackson wanted to
do in the North, had he not been killed in battle. How Sir Edmund Allenby
stopped the Germans in the Middle East, with a little help from T.E.
Lawrence and his Arabs. How Mao Zedong led the Red Army during the
Long March. How Heinz Guderian, Erich von Manstein, and Erwin
Rommel realized what tanks were really good for, and the use they made
of them. How Douglas MacArthur won at Inchon and why he failed
spectacularly afterwards.

The book ends with a summary of the principles discussed throughout the
book:

• Operate on the line of least expectation and least resistance. Figure
  out where the enemy doesn’t expect you to go–and go that way. France
  fell so quickly at the beginning of WWII because no one thought the
  Germans could bring tanks through the forest of Ardennes.

• Maneuver to the rear of the enemy. Your enemy’s morale will suffer
  when he realizes that you’re sitting across his supply lines; and if
  he’s too far from home his army might just disintegrate. That’s what
  happened to the North Korean army in South Korea after MacArthur’s
  invasion of Inchon.

• Occupy the central position. That is, if your enemy has two forces,
  maneuver to a point directly between them. This ensures that you can
  deal with either one before the other joins with it, thus “defeating
  the enemy in detail”. Napoleon was a master at this in his early
  days; once he became emperor, though, he lost his subtlety and tried
  to win all his battles with brute force.

• Follow a “plan with branches”. Uncertainty and misdirection are your
  allies. Therefore, maneuver in two or more columns, keeping the columns
  far enough apart that the enemy can’t guess what your true objective is, but
  close enough together that they can support each other at need. The
  enemy won’t know what to defend, and will likely end up dividing his
  forces to defend a number of spots. No less than three times during Sherman’s
  march north from Atlanta the Confederates split their forces between
  the two cities his columns appeared to be approaching; and in each case
  Sherman marched his troops right through the middle and captured a
  third, undefended city.

• Don’t attack prepared and well-defended positions. Instead, make the
  enemy leave their positions and come to you. Scipio Africanus conquered
  Carthage not by a frontal assault on the city, but by marching into and
  burning the city’s agricultural hinterland. The Carthaginian army was
  forced to follow after, or else the city would starve.

• Don’t get pinned down in fortifications. If you’re holed up in a fort,
  you’re effectively out of the battle.

• Where the enemy’s army isn’t is often more important than
  where it is.

All in all it’s a fascinating book, and for my purposes useful as well.
I recommend it.