By trying to convert a Confederate resource to Union advantage, emancipation thus became a crucial part of the North's national strategy. But the idea of putting arms in the hands of black men provoked even greater hostility among Democrats and border state Unionists than emancipation itself. In August 1862, Lincoln told delegates from Indiana who offered to raise two black regiments that "the nation could not afford to lose Kentucky at this crisis" and that "to arm the negroes would turn 50,000 bayonets from the loyal border States against us that were for us."
Three weeks later, however, the president quietly authorized the War Department to begin organizing black regiments on the South Carolina Sea Islands. And by March 1863, Lincoln had told his military governor of occupied Tennessee that "the colored population is the great available and yet unavailed of, force for restoring the Union. The bare sight of fifty thousand armed, and drilled black soldiers on the banks of the Mississippi, would end the rebellion at once. And who doubts that we can present that sight, if we but take hold in earnest."
This prediction proved overoptimistic. But in August 1863, after black regiments had proved their worth at Fort Wagner and elsewhere, Lincoln told opponents of their employment that in the future "there will be some black men who can remember that, with silent tongue, and clenched teeth, and steady eye, and well-poised bayonet, they have helped mankind on to this great consummation; while, I fear, there will be some white ones, unable to forget that, with malignant heart, and deceitful speech, they have strove to hinder it."
Lincoln also took a more active, hands-on part in shaping military strategy than presidents have done in most other wars. This was not necessarily by choice. Lincoln's lack of military training inclined him at first to defer to General in Chief Winfield Scott, America's most celebrated soldier since George Washington. But Scott's age (75 in 1861), poor health and lack of energy placed a greater burden on the president. Lincoln was also disillusioned by Scott's March 1861 advice to yield both Forts Sumter and Pickens. Scott's successor, Gen. George B. McClellan, proved an even greater disappointment to Lincoln.
In early December 1861, after McClellan had been commander of the Army of the Potomac for more than four months and had done little with it except conduct drills and reviews, Lincoln drew on his reading and discussions of military strategy to propose a campaign against Confederate Gen. Joseph E. Johnston's army, then occupying the Manassas-Centreville sector 25 miles from Washington. Under Lincoln's plan, part of the Army of the Potomac would feign a frontal attack while the rest would use the Occoquan Valley to move up on the flank and rear of the enemy, cut its rail communications and catch it in a pincer movement.
It was a good plan; indeed it was precisely what Johnston most feared. McClellan rejected it in favor of a deeper flanking movement all the way south to Urbana on the Rappahannock River. Lincoln posed a series of questions to McClellan, asking him why his distant-flanking strategy was better than Lincoln's short-flanking plan. Three sound premises underlay Lincoln's questions: first, the enemy army, not Richmond, should be the objective; second, Lincoln's plan would enable the Army of the Potomac to operate near its own base (Alexandria) while McClellan's plan, even if successful, would draw the enemy back toward his base (Richmond) and lengthen the Union supply line; and third, "does not your plan involve a greatly larger expenditure of time...than mine?"
McClellan brushed off Lincoln's questions and proceeded with his own plan, bolstered by an 8–4 vote of his division commanders in favor of it, which caused Lincoln reluctantly to acquiesce. Johnston then threw a monkey wrench into McClellan's Urbana strategy by withdrawing from Manassas to the south bank of the Rappahannock—in large part to escape the kind of maneuver Lincoln had proposed. McClellan now shifted his campaign all the way to the Virginia peninsula between the York and James rivers. Instead of attacking a line held by fewer than 17,000 Confederates near Yorktown with his own army, then numbering 70,000, McClellan, in early April, settled down for a siege that would give Johnston time to bring his whole army down to the peninsula. An exasperated Lincoln telegraphed McClellan on April 6: "I think you better break the enemies' line from York-town to Warwick River, at once. They will probably use time, as advantageously as you can." McClellan's only response was to comment petulantly in a letter to his wife that "I was much tempted to reply that he had better come & do it himself."
In an April 9 letter to the general, Lincoln enunciated another major theme of his military strategy: the war could be won only by fighting the enemy rather than by endless maneuvers and sieges to occupy places. "Once more," wrote Lincoln, "let me tell you, it is indispensable to you that you strike a blow. You will do me the justice to remember I always insisted, that going down the Bay in search of a field, instead of fighting at or near Manassas, was only shifting, and not surmounting, a difficulty—that we would find the same, or equal intrenchments, at either place. The country will not fail to note—is now noting—that the present hesitation to move upon an intrenched enemy, is but the story of Manassas repeated."
But the general who acquired the nickname of Tardy George never learned that lesson. The same was true of several other generals who did not live up to Lincoln's expectations. They seemed to be paralyzed by responsibility for the lives of their men as well as the fate of their army and nation. This intimidating responsibility made them risk-averse. This behavior especially characterized commanders of the Army of the Potomac, who operated in the glare of media publicity with the government in Washington looking over their shoulders. In contrast, officers like Ulysses S. Grant, George H. Thomas and Philip H. Sheridan got their start in the western theater hundreds of miles distant, where they worked their way up from command of a regiment step by step to larger responsibilities away from media attention. They were able to grow into these responsibilities and to learn the necessity of taking risks without the fear of failure that paralyzed McClellan.
Meanwhile, Lincoln's frustration with the lack of activity in the Kentucky-Tennessee theater had elicited from him an important strategic concept. Generals Henry W. Halleck and Don C. Buell commanded in the two western theaters separated by the Cumberland River. Lincoln urged them to cooperate in a joint campaign against the Confederate army defending a line from eastern Kentucky to the Mississippi River. Both responded in early January 1862 that they were not yet ready. "To operate on exterior lines against an enemy occupying a central position will fail," wrote Halleck. "It is condemned by every military authority I have ever read." Halleck's reference to "exterior lines" described the conundrum of an invading or attacking army operating against an enemy that holds a defensive perimeter resembling a semi-circle—the enemy enjoys the advantage of "interior lines" that enables it to shift reinforcements from one place to another within that arc.