J.G. Randall showed that a world-class scholar could admire Lincoln and McClellan; Clifford Dowdey shows us that an appreciation, even veneration, of McClellan is possible for Lee admirers. A wonderful break from the usual, displaying a mastery of the material.
To simplify a subtle book: McClellan (heroically) dominates the early parts, with Johnston and Magruder as fools and Lincoln and Stanton as Macbeth's witches. Lee's greatness is in his response to the crisis McClellan represents and Lee's tragedy is his first success, which prolongs the war and empowers the South's worst enemies. The author's treatment of the North's and South's politics adds a vivid dimension that puts his competitors in the shade.
Dowdey fails only twice, first in the matter of comparative (force) strengths, second in the business of McClellan's change of base and his consequent state of mind. The book sets a standard, regardless.