by America's preeminent military historian, James McPherson (professor emeritus, Princeton) is the latest in the hagiographies of Lincoln as military leader which stretch back at least to T. Harry Williams.

Ironically, Lincoln's greatest failing was one of his most attractive qualities, his humility. In dealing w/ generals Lincoln was acutely aware of his lack of a military education. What he apparently never understood was that his generals were little better off. West Point was not a "military acadeny," but rather it was an engineering school training officers to perform the jobs that were traditional in peacetime in an Army which even in war had never seen anything more than small unit engagements. Lee and McClellan were both able engineers of fortifications and other emplacements. The South was blessed in that Lee was also a superb leader of men. The North was cursed in that McClellan was an able engineer w/ great personal charm and a huge ego who was a moral coward unwilling and unable to close w/ an opponent and fight. And McClellan was the best of the lot until finally Grant, Sherman and Sheridan showed up. (Note that all of them were essentially self-taught in handling major military forces since West Point provided no training in that.)

From the outset Lincoln seems to have understood the strategic lessons to which his generals were blind before the emergence of Grant, Sherman and Sheridan. But he was too humble and uncertain to do what was necessary: call his generals together, ask who was willing to fight battles, and fire all the others. Had Grant, Sherman and Sheridan been available for leadership in 1861 the war would have been over in 1862.
(Of course Grant, Sherman and Sheridan needed seasoning and experience of major battles. But so did Lee.)