IN SEARCH OF A MISSIONMatt Yglesias nails ithttp://www.matthewyglesias.com/archives/2006/12/escalating_silence/Roughly speaking, the fixed point of the president's thinking is an unwillingness to admit that the venture has failed. For a long time the best way to do that was to simply deny that there was a problem. Political strategy for the midterms, however, dictated that the president had to