Everybody knew that President Bush had to dedicate a good portion of his SOTU address to the war in Iraq. Democrats knew this and it's why they chose Senator Penis Mouth to give the rebuttal.
Webb is a Vietnam vet which gives him infallibility and a figmental shield that appears whenever he's talking about the war. If you subscribe to this liberal "chickenhawk" argument then you should also believe W. Thomas Smith Jr's word is indispensible as well.
Smith's piece, Webb vs. Facts, is over at National Review-- check it out.