As Americans observe the anniversary of the attack on Pearl Harbor today, much will be said and written about the necessity for us to remain vigilant against our enemies. But the Japanese sneak attack that forced the United States into World War II carried with it a deeper warning, reinforced decades later when terrorists assaulted America on Sept. 11, 2001.
Prior to both attacks, U.S. officials thought they were aware of threats. But in 1941, the Japanese were vastly underestimated - and it was thought an air attack on the fleet in Hawaii would be difficult, if not impossible.
U.S. intelligence officials thought they understood the threat from al-Qaida before 9/11, too. Again, however, the terrorist group's capabilities were not understood.
In both situations, complacency was not the problem. It was, instead, a sort of arrogant over-confidence not backed by reality.
What happened on and after 9/11 was bad enough - but the consequences of Dec. 7, 1941, were much worse. Today, let us as Americans remember that identifying an enemy is not the same as knowing him.