UNIDENTIFIED CNN CORRESPONDENT: Scott Sperry from Alpharetta, Georgia asks, what is a stage four DEFCON alert? What are the other stages of alert?</s>MAJ. GEN. DONALD SHEPPERD, (RET.) CNN MILITARY ANALYST: In the event of a national emergency there are seven different alert conditions separated into five defense conditions called DEFCON for short and two emergency conditions called EMERCONS for short. Normal peacetime readiness is DEFCON five. When September the 11th occurred, U.S. forces were put on DEFCON four, which means increased ratings. You review your alert rosters; you put more guards on the gate; you deny access to certain things and then it can be stepped up all the way to DEFCON one, which is wartime conditions. And once, in our history, we have gone to DEFCON two. That was during the Cuban missile crisis when strategic alert command was put on alert and even had their airplanes airborne. Now the two emergency conditions are defense emergency and the air defense emergency. And defense emergency means that U.S. or allied forces have come under attack anywhere in the world. It's missiles in the air, if you will, all designed around the nuclear missile
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