As a war leader, Lincoln employed the style that had served him as a politician—a description of himself, incidentally, that he was not ashamed to accept. He preferred to react to problems and to the circumstances that others had created rather than to originate policies and lay out long-range designs. In candor he would write, “I claim not to have controlled events, but confess plainly that events have controlled me.” His guiding rule was “My policy is to have no policy.” It was not that he was unprincipled; rather, he was a practical man, mentally nimble and flexible, and, if one action or decision proved unsatisfactory in practice, he was willing to experiment with another.

From 1861 to 1864, while hesitating to impose his ideas upon his generals, Lincoln experimented with command personnel and organization. Accepting the resignation of Scott (November 1861), he put George B. McClellan in charge of the armies as a whole. After a few months, disgusted by the slowness of McClellan (“He has the slows,” as Lincoln put it), he demoted him to the command of the Army of the Potomac alone. He questioned the soundness of McClellan’s plans for the Peninsular Campaign, repeatedly compelled McClellan to alter them, and, after the Seven Days’ Battles to capture Richmond, Virginia (June 25–July 1, 1862), failed, ordered him to give them up. Then he tried a succession of commanders for the army in Virginia—John Pope, McClellan again, Ambrose E. Burnside, Joseph Hooker, and George Gordon Meade—but was disappointed with each of them in turn. Meanwhile, he had in Henry W. Halleck a general in chief who gave advice and served as a liaison with field officers but who shrank from making important decisions. For nearly two years the Federal armies lacked effective unity of command. President Lincoln, General Halleck, and War Secretary Edwin M. Stanton acted as an informal council of war. Lincoln, besides transmitting official orders through Halleck, also communicated directly with the generals, sending personal suggestions in his own name. To generals opposing Robert E. Lee, he suggested that the object was to destroy Lee’s army, not to capture Richmond or to drive the invader from Northern soil.

Finally Lincoln looked to the West for a top general. He admired the Vicksburg Campaign of Ulysses S. Grant in Mississippi. Nine days after the Vicksburg surrender (which occurred on July 4, 1863), he sent Grant a “grateful acknowledgment for the almost inestimable service” he had done the country. Lincoln sent also an admission of his own error. He said he had expected Grant to bypass Vicksburg and go on down the Mississippi, instead of crossing the river and turning back to approach Vicksburg from the rear. “I feared it was a mistake,” he wrote in his letter of congratulations. “I now wish to make the personal acknowledgment that you were right, and I was wrong.”

In March 1864 Lincoln promoted Grant to lieutenant general and gave him command of all the federal armies. At last Lincoln had found a man who, with such able subordinates as William T. Sherman, Philip Sheridan, and George H. Thomas, could put into effect those parts of Lincoln’s concept of a large-scale, coordinated offensive that still remained to be carried out. Grant was only a member, though an important one, of a top-command arrangement that Lincoln eventually had devised. Overseeing everything was Lincoln himself, the commander in chief. Taking the responsibility for men and supplies was Secretary of War Stanton. Serving as a presidential adviser and as a liaison with military men was Halleck, the chief of staff. And directing all the armies, while accompanying Meade’s Army of the Potomac, was Grant, the general in chief. Thus Lincoln pioneered in the creation of a high command, an organization for amassing all the energies and resources of a people in the grand strategy of total war. He combined statecraft and the overall direction of armies with an effectiveness that increased year by year. His achievement is all the more remarkable in view of his lack of training and experience in the art of warfare. This lack may have been an advantage as well as a handicap. Unhampered by outworn military dogma, Lincoln could all the better apply his practical insight and common sense—some would say his military genius—to the winning of the Civil War.

There can be no doubt of Lincoln’s deep and sincere devotion to the cause of personal freedom. Before his election to the presidency he had spoken often and eloquently on the subject. In 1854, for example, he said he hated the Douglas attitude of indifference toward the possible spread of slavery to new areas. “I hate it because of the monstrous injustice of slavery itself,” he declared. “I hate it because it deprives our republican example of its just influence in the world; enables the enemies of free institutions with plausibility to taunt us as hypocrites.” In 1855, writing to his friend Joshua Speed, he recalled a steamboat trip the two had taken on the Ohio River 14 years earlier. “You may remember, as I well do,” he said, “that from Louisville [Kentucky] to the mouth of the Ohio there were, on board, ten or a dozen slaves, shackled together with irons. That sight was a continual torment to me; and I see something like it every time I touch the Ohio, or any other slave-border.”

Yet, as president, Lincoln was at first reluctant to adopt an abolitionist policy. There were several reasons for his hesitancy. He had been elected on a platform pledging no interference with slavery within the states, and in any case he doubted the constitutionality of federal action under the circumstances. He was concerned about the possible difficulties of incorporating nearly four million African Americans, once they had been freed, into the nation’s social and political life. Above all, he felt that he must keep the border slaveholding states in the Union, and he feared that an abolitionist program might impel them, in particular his native Kentucky, toward the Confederacy. So he held back while others went ahead. When General John C. Frémont and General David Hunter, within their respective military departments, proclaimed freedom for the enslaved people of disloyal masters, Lincoln revoked the proclamations. When Congress passed confiscation acts in 1861 and 1862, he refrained from a full enforcement of the provisions authorizing him to seize enslaved property. And when Horace Greeley in the New York Tribune appealed to him to enforce these laws, Lincoln patiently replied (August 22, 1862):

My paramount object in this struggle is to save the Union, and is not either to save or to destroy slavery. If I could save the Union without freeing any slave I would do it; and if I could save it by freeing all the slaves I would do it; and if I could save it by freeing some and leaving others alone, I would also do that.

Meanwhile, in response to the rising antislavery sentiment, Lincoln came forth with an emancipation plan of his own. According to his proposal, the enslaved were to be freed by state action, the slaveholders were to be compensated, the federal government was to share the financial burden, the emancipation process was to be gradual, and the freed people were to be colonized abroad. Congress indicated its willingness to vote the necessary funds for the Lincoln plan, but none of the border slaveholding states were willing to launch it, and in any case few Black American leaders desired to see their people sent abroad. Lincoln signed the District of Columbia Compensated Emancipation Act into law on April 16, 1862, resulting in the freedom of about 3,000 enslaved people in the nation’s capital.

While still hoping for the eventual success of his gradual plan, Lincoln took quite a different step by issuing his preliminary (September 22, 1862) and his final (January 1, 1863) Emancipation Proclamation. This famous decree, which he justified as an exercise of the president’s war powers, applied only to those parts of the country actually under Confederate control, not to the loyal enslaving states nor to the federally occupied areas of the Confederacy. Directly or indirectly the proclamation brought freedom during the war to fewer than 200,000 enslaved persons. Yet it had great significance as a symbol. It indicated that the Lincoln government had added freedom to reunion as a war aim, and it attracted liberal opinion in England and Europe to increased support of the Union cause. When news of the Emancipation Proclamation finally reached the distant state of Texas on June 19, 1865—more than two years after Lincoln had issued the proclamation—the newly freed slaves immediately began to celebrate with prayer, feasting, song, and dance, spurring the national holiday known as Juneteenth or Emancipation Day.

(Read Charles Blow’s Britannica essay on the Juneteenth holiday.)

Lincoln himself doubted the constitutionality of his step, except as a temporary war measure. After the war, the enslaved people freed by the proclamation would have risked re-enslavement had nothing else been done to confirm their liberty. But something else was done: the Thirteenth Amendment was added to the Constitution, and Lincoln played a large part in bringing about this change in the fundamental law. Through the chairman of the Republican National Committee he urged the party to include a plank for such an amendment in its platform of 1864. The plank, as adopted, stated that slavery was the cause of the rebellion, that the president’s proclamation had aimed “a death blow at this gigantic evil,” and that a constitutional amendment was necessary to “terminate and forever prohibit” it. When Lincoln was reelected on this platform and the Republican majority in Congress was increased, he was justified in feeling, as he apparently did, that he had a mandate from the people for the Thirteenth Amendment. The newly chosen Congress, with its overwhelming Republican majority, was not to meet until after the lame duck session of the old Congress during the winter of 1864–65. Lincoln did not wait. Using his resources of patronage and persuasion upon certain of the Democrats, he managed to get the necessary two-thirds vote before the session’s end. He rejoiced as the amendment went out to the states for ratification, and he rejoiced again and again as his own Illinois led off and other states followed one by one in acting favorably upon it. (He did not live to rejoice in its ultimate adoption.)

Lincoln deserves his reputation as the Great Emancipator. His claim to that honor, if it rests uncertainly upon his famous proclamation, has a sound basis in the support he gave to the antislavery amendment. It is well founded also in his greatness as the war leader who carried the nation safely through the four-year struggle that brought freedom in its train. And, finally, it is strengthened by the practical demonstrations he gave of respect for human worth and dignity, regardless of color. During the last two years of his life he welcomed African Americans as visitors and friends in a way no president had done before. One of his friends was the distinguished formerly slaved Frederick Douglass, who once wrote: “In all my interviews with Mr. Lincoln I was impressed with his entire freedom from prejudice against the colored race.”