Why was shuttle terminated?

Why was the shuttle terminated?
My best summary of why the Shuttle program termination was announced in 2005 by President Bush and allowed to occur in 2012 by the Obama Administration would have to combine several factors. No clear rationale for termination was ever given by either the Bush or Obama Administrations that spanned the 7 year phase out leading to the final flight in 2011.
The Bush Administration announced in its "Vision for Space Exploration" that the venerable Shuttle would be terminated at a future date (2010) and that we would embark on a Lunar/Mars program. This Lunar/Mars program decision was not well thought out and proved to be a folly. It spawned a program called Constellation that expired due to poor engineering, poor planning, poor execution and lack of funding support. It was properly cancelled by the Obama administration but pieces linger on due to confused support by the Congress and the Obama Administration.
Clearly the two fatal accidents led to a perception that the Shuttle was unsafe. Most discussion of cost led to the perception that the Shuttle was too costly. The chronological age of the system led to a perception that the Shuttle was too old. These loose perceptions were never properly responded to by NASA. In fact they were instituted by many key NASA officials. For example when Mr. Griffin became the NASA Administrator he quickly proclaimed that the Shuttle and Space Station were a mistake and he was here to correct this mistake. He promptly wasted about 12 Billion dollars and five years. Therefore perception became fact and the Shuttle program was allowed to fade away gracefully over several years with no responsible study as to why. The Nation quietly found its self without a means for launching people into space. Depending on the Russian Soyuz system was the only option available to continue manning the Space Station.
The "Vision for Space Exploration" announcement by the Bush Administration following the second Shuttle accident and the confusion left by the Columbia Accident Investigation Board essentially set the country up for an inadvertent "Bait and switch" situation. Let's terminate the venerable Shuttle, go back to the moon with an Apollo type throw away system and on to Mars. We can do this within current budget levels. Once the bait was taken the Shuttle was allowed to terminate and the idea of" Apollo on Steroids" disappeared. We are now in a "Down Time" and can hope for commercial to get us back in the space business with some limited capability. This so called "commercial" program started by NASA during the Bush Administration and wisely continued by the Obama Administration should be encouraged and properly supported. It is now May 2012, 42 years after establishing the Shuttle Program as a formal NASA endeavor. We are temporarily out of the manned launch business.
We need an Administration that can plan to use our available Space budget wisely. We should continue with commercial and carefully review the reasoning behind SLS/Orion. The budget level for NASA and all high cost program efforts need careful Executive and Legislative Branch understanding. NASA'S Manned Exploration Program is not effectively planned. Robert Thompson, Program Manager

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