There are two important lessons to be learned from the bungled attempt on Christmas Day to cause an explosion on a Northwest Airlines flight from Amsterdam to Detroit: (1) the need to remain vigilant against the threat posed by terrorists, and (2) recognition of the importance of Yemen, a state that has proved to be a breeding ground for extremists and risks becoming another failed state. It is vitally important that the proper conclusions be drawn from the failed attack and that hysterical over-reactions be avoided.

On Christmas day, Umar Farouk Abdulmutallab, the quiet son of a prominent Nigerian banker, flew from Lagos to Amsterdam, where he then boarded a flight for Detroit. Just before that flight landed, Abdulmutallab allegedly tried to ignite an incendiary device hidden in his underwear. Alert passengers grabbed him as the device fizzled and managed to avert an explosion.

Investigation of the incident revealed a number of security failures. Abdulmutallab's father, alarmed by his son's behavior — he had cut off communication with his family, gone to Yemen and was associating with extremists — contacted U.S. officials in Nigeria to warn them. This got the young man on a watch list, but did not result in termination of his visa for the U.S., nor did it warrant placement on a no-fly list. Intelligence officials did not cross-reference this data with an earlier warning about a Nigerian being trained for an al-Qaida attack. Having studied in the United Kingdom, British intelligence apparently had information on Abdulmutallab, but it is not clear what they shared with their counterparts in the U.S., Europe and Africa. Plainly, even after the appalling failures of Sept. 11, 2001, intelligence agencies are not communicating with each other.