In the late 40s CAP was involved in a Nuclear War exercise (Operation Comet) with the Civilian Defense and the US Army/Air Force. See here:
http://www.scribd.com/doc/35142291/1949-Anti-Aircraft-Journal-Aug
Let it load and go to page 35 and 36. It's an amazing article. Just jaw dropping when you think about it.
1. Because nuclear war was being considered and exercised before the Soviet Union exploded their first bomb on August 29, 1949.
2. This Exercise was extensive, not so much in area as breadth and depth of competence in the operation.
3. CAP was involved at numerous levels and at all times.
This magazine (Anti-Aircraft Journal 1949) is from the extensive collection of Lt. Col. Mark Hess or the GAWG. I thank him for allowing its use in this thread.