From my understanding, parts to this jet are made all over the US so its beneficial for US to keep paying which retains jobs in so many states.

This plane is highly political and its not really easy to "pull the plug" or not pay since many states will loose workforce.

Robert Gates wrote a chapter in his book about it that was fascinating.

http://www.amazon.com/Duty-Memoirs-Secretary-at-War/dp/03079...