I think they’ve been preparing for years. It is interesting that this thread was preceeded by this one:
Massive U.S. Military Buildup Reported Around Iran; Up To 100,000 Troops Ready By March
http://www.freerepublic.com/focus/f-news/2841603/posts
zone of immunity
I think it is also called a “point of no return”. I believe that just before a similar “zone of immunity” Israel peformed Operation Babylon: http://en.wikipedia.org/wiki/Operation_Opera
The (unnamed sources in the) Admin added something for this article. It is VERY non-committal about MAYBE aiding Israel, but only AFTER their cities are hit by Iran.