WHY VANDENBURG WAS NEVER USED TO LAUNCH THE SHUTTLE.

In the late 70's the USAF, built a 4 Billion dollar launch facility for the Space Shuttle, at Vandenberg Air Force Base on the central coast of California. This facility was never used to launch the shuttle and the weapons payloads the shuttle was designed to put into orbit. That's because the Air Force decided to use Area-51 instead. Where the shuttle was launched from a modified shuttle carrier plane that used nuclear thermal rockets and nuclear turbojet engines. Launch from the carrier plane is actually a better move allowing the Shuttle to rendezvous more easily with satellites in orbit. It also allowed the military to launch the shuttle silently and out of the sight of spectators.  

In 1975 NASA approved Vandenburg as it's West Coast launch site. This parallelled the construction of Hangar 18 at Area-51. Vandenburg was a budgetary feint, the cover for the construction of HANGAR 18.