Thirteen.

This is coolbert:

Which of Dupuy's thirteen timeless verities of combat are most applicable and pertinent to the Battle of Iwo Jima?

[emphasis here on the words applicable and pertinent!!]

* #2 Defensive strength is greater than offensive strength.

Defense is the stronger form of combat. On the defensive, you can accomplish more with less and do it easier than when on the offensive. That was true for Kuribayashi and his defenders at Iwo.

* #6 Defenders' chances of success are directly proportional to fortifications strength.

Having buried deep gave the Jap defender at Iwo a decided boost.

* #7 An attacker willing to pay the price can always penetrate the strongest defenses.

Marine commanders at Iwo were determined and willing to pay the price for victory. Also had resolute and high determined Marines under their command.

[the average age of a Marine at Iwo was nineteen years old!!!

* #9 Superior combat power always wins.

The Marines obviously had a vast amount of combat power at their disposal [land, sea, air combined]. And needed it. Could call upon whatever reserve strength they needed to accomplish the task at hand. As strong as the Japanese combat power was, it was not even a comparison to what the Marines could call upon.

coolbert.