The first presidential debate of 2012 is now behind us. And Republican challenger Mitt Romney won it handily. No one challenges this verdict. Even President Obama’s most ardent supporters concede it by way of the truly laughable excuses to which they’ve resorted in accounting for the decisive drubbing that their candidate received. But while the conventional wisdom concerning the victor is sound enough, the conventional wisdom concerning the debate’s loser is not so much. Obama, we are told, was “off his game.” From Denver’s altitude to personal family issues, every conceivable rationale has been offered by the President’s admirers to...