President Garfield: From Radical to Unifier by C. W. Goodyear:
Experienced soldiers had well-founded doubts about such officers; it was hard to put faith in a commander who had bought a uniform yesterday, and whose grasp of military strategy came mostly from borrowed library books. A stereotype soon formed of a small-town politician buckling on a sword, rushing to the frontlines, then hurrying home to trade their brief, dubious service for higher office—as a gambler might cash in a hastily won stack of chips. A name was attached to this caricature: “‘Political general’ became almost a synonym for incompetency, especially in the North,” a historian would judge.
Yet from the instant Garfield learned of the attack on Fort Sumter, he set himself on becoming just such an officer. Nor was Garfield the only politician in Columbus to do so; he and Jacob Cox had a confidential conversation “over the prospects of the country and the future of our own lives.” Recognizing that joining the army would benefit both causes, the pair then divvied up books on battlefield tactics and Napoleonic history—dabbing the finishing touches on an image of two would-be political generals getting to work.