Communications with some 50 nuclear missiles were disrupted for 45 minutes on Saturday, making it more difficult to launch them and sending the military scrambling to determine the cause of the incident, according to defense officials. The incident was significant enough that President Barack Obama was briefed on it this week. A defense official said a power failure disrupted communications between a control center and the missiles at F.E. Warren Air Force Base in Wyoming. There was no danger of an accidental launch, officials said, and the Air Force had eyes on the missiles at all times. "There was no threat to the public," said the defense official. The cause of the power failure remains un known, but it is not believed to be malicious. Adm. Michael Mullen, the chairman of the joint chiefs of staff, notified Defense Secretary Robert Gates of the incident. The incident was first reported by the Atlantic on its website on Tuesday. Another official said the cause of the incident was being analyzed. "The missiles were protected by multiple, redundant safety security and control features," said a military official. In 2008, a series of problems with nuclear weapons and parts, including the accidental transport of a weapon across the U.S., led Defense Secretary Gates to fire the Air Force secretary and chief of staff. The current Air Force leadership has put more emphasis on improving nuclear readiness and stewardship of the arsenal. It has restored funding, increased the number of inspections, and tried to increase the prestige of airmen and officers working in the nuclear field. The Atlantic reported that the squadron of ICBMs was in "LF Down" status, which means the airmen in the missile bunkers could not communicate with the missiles. The missiles still could be launched, but only by airborne command and control platforms. Although the missiles at Warren Air Force base represent a large proportion of the ICBM arsenal, the defense official said that at no time was Mr. Obama without a nuclear-launch capability. (WSJ)