When he took office, Lincoln had gone about as far as he thought he could go on the issue of slavery. He'd approved a policy that designated runaway slaves "contraband" of war and even eliminated slavery in Washington, D.C., which was under the direct control of the federal government.
Lincoln had rescinded an order, though, by the general overseeing Missouri in 1861 that would have liberated all the slaves in the state. "I think there is a great danger," Lincoln wrote in a letter before relieving the general of his command, that the "confiscation of property, and the liberating of slaves of traitorous owners, will alarm our Southern Union friends, and turn them against us."
Lincoln thought he had a better idea. In the spring and summer of 1862, more than a year into his first term, he met with representatives of the border states—Delaware, Maryland, West Virginia, Kentucky, and Missouri—and asked them to adopt a plan of gradual, compensated emancipation on their own. In Delaware, he'd floated the idea of the federal government paying slave owners $400 per slave, with all adult slaves over 35 being freed immediately. Lincoln suggested the rest of the slaves should be freed in 10 years.
This, historians say, was a critical moment for Lincoln. While he was struggling to maintain the loyalty of the border states, after all, abolitionists were practically battering down his door. After he had abolished slavery in the District of Columbia, antislavery advocates worried that the president's "face was turned toward Zion, but he seemed to move with leaden feet." The abolition movement was gaining political strength, deluging Congress with petitions calling for the end of slavery. Black leaders like Frederick Douglass and Harriet Tubman were publicly challenging Lincoln to take action.
Lincoln's political allies, meanwhile, were also doing their utmost in letters and personal meetings to convince him that emancipation would help the war effort. Charles Sumner, a Massachusetts senator who worried that radical Republicans would split with Lincoln if he did not act, may have had the biggest effect. Sumner spent months in 1861 and 1862 trying to make Lincoln understand that emancipation would have far-reaching consequences, cutting off the Confederacy from potential allies in Europe—who opposed slavery—while also drastically undermining the Southern economy. After one meeting with Sumner, Lincoln seemed to cave in: "Well, Mr. Sumner," he said, "the only difference between you and me on this subject is a difference of a month or six weeks in time."
The turning point came in the summer of 1862, when the border states rejected, once and for all, Lincoln's proposals of gradual emancipation. "This was a decisive moment," says Ronald White, a visiting professor of history at UCLA and author of A. Lincoln, a new biography. Though the Confederate army was still strong, after a year of warfare, the border states were no longer in serious danger. Slaves had begun to escape from the South by the tens of thousands, and Lincoln, who had come into office determined to uphold the Constitution, recognized that emancipation could be legally justified as a wartime seizure of enemy "property."
"He got kind of fed up with the border states," says McPherson. "Clearly, the radical wing of the Republican Party was pushing for this virtually since the beginning of the war. And the longer the war went on, the more plausible their argument seemed: You can't win a war against an enemy that's sustained by and is fighting for slavery without striking against slavery itself."
The politics of slavery, in other words, had changed, and Lincoln, historians believe, was among the first to recognize it. "He was constantly goaded on this issue," says Douglas Wilson, codirector of the Lincoln Studies Center at Knox College in Illinois. Eventually, Lincoln realized that the political ground had shifted beneath him.