Regardless of the wisdom of his policies, Bush has been a failure as a war leader because of his atrocious communication skills.
Lincoln and Churchill were handed disastrous military defeats (First Bull Run, Seven Days, Second Bull Run, Fredericksburg, the Battle of France) and verbally rallied their Home Fronts to final Victory.
Bush was handed military victories and verbally lost the Home Front to the point that the U.S. is one Presidential election away from unilaterally declaring defeat and turning tail to run. Before Obama self-destructed, the odds were that the war would be lost by 2009.
Militarily, we’re winning the war. That hardly makes him a failure. When the media were crucifying President Reagan, over 60% of the country wasn’t forming opinions on current events from the statements and humor of David Letterman, Ophra Winfrey, MTV or Comedy Central. He’s bad ad communicating, but not THAT bad.