The Day World War II Began for the U.S.

Seventy years ago today, the United States Pacific fleet was attacked by Japanese naval aircraft. Twenty ships were damaged or destroyed, including four battleships sunk or destroyed.

Seventy years later, the USS Arizona still weeps.

There is an interesting sidelight to the attack and the sinking of the Arizona. In battle, the Japanese navy used torpedoes and naval artillery to sink enemy ships. They apparently did not have penetrators — armor piercing bombs — available for use. In the Pearl Harbor attack, the primary objective was to sink all the U.S. battleships and aircraft carriers — or as many of them as they could. They would want to use their bombers in that effort as well as their torpedo planes. To do that, they made their own penetrating bombs, adapting 16" artillery shells for that purpose. It was one of these improvised bombs that destroyed the Arizona and turned it into a cemetery.