Exploring Lincoln's political and military leadership provides the analytical thread in the book's narrative of the White House years. Indeed, it is in the president's determined coordination of the competing claims of political and military strategy that Gienapp locates the cornerstone of Lincoln's success. Lincoln saw, in a way that his generals rarely did, that military policy could not be pursued in a political democracy without attending to the hopes and fears of the people at large. McClellan's sluggishness in 1862 notoriously did the administration no political favors. Even Ulysses S. Grant, no slouch, had to be taught the lesson. The president brought him east in 1864 and insisted that he keep northern Virginia his area of operation: that was what the political public expected.
Lincoln had no previous executive experience to bring to the task of political leadership itself, but this limitation was largely offset by a lifetime's immersion in party management and a rare understanding of what made politicians tick. Recognizing how important it was to keep his Republican-Union party united and as broad-based as possible, he spent much of his time oiling the party machinery and using government jobs to keep its workers loyal (even though, naturally, there were "more horses than oats"). This concern similarly conditioned his shaping of policy. In his schemes for both emancipation and reconstruction he was bent on forging as wide a political consensus as he could, one which would at least draw in the full range of Republicans—radical, moderate and conservative—if not opposition Democrats.
Lincoln's noncombatant service in the Black Hawk war 30 years earlier, his only martial experience, scarcely equipped him for the task of military leadership in an internecine civil conflict. But as commander-in-chief he was determined to be more than a sideline onlooker, and his earnest attempts to grapple with military theory and with developing an effective chain of command showed that instinctive grasp of essentials which so many of his generals lacked. Gienapp traces the evolution of Lincoln's strategy, from the prosecution of limited warfare that would leave the South's institutions intact to a hard war policy that entailed an assault on slavery, the Confederacy's infrastructure, and—finally, through Sherman's marches—its psychological well-being.
Gienapp does not hide his admiration for Lincoln's "accomplished and extraordinary" style of leadership and the speed with which he established himself as master of his administration and kept control of the social revolution launched by the war. The president readily left to Congress what he judged properly to lie within its own sphere, including legislation on economic issues, but he forcefully took control of war policy, including emancipation and reconstruction. He swiftly achieved mastery of his cabinet and, though ready to delegate (notably, financial matters to Chase and foreign affairs to Seward), he was quick to intervene when larger strategic objectives were threatened, as during the Anglo-American crisis over the Trent.
Lincoln's assumption of new executive powers, whether to secure the border, raise troops, or prosecute a harder war, was "breathtaking": unauthorized use of the Treasury; suspension of habeas corpus; and government by presidential proclamation. Resolute over ends but flexible over means, he took crucial decisions by himself, relying on his own judgment. Lincoln's legendary antipathy to quarrels and political vendettas was just one expression of an ability to work with men of diverse outlooks and to endure criticism and ridicule without falling himself into self-defeating small-mindedness. And throughout the struggle he exhibited an extraordinary physical and mental toughness that kept him resilient after even the most desperate setbacks.






