In all the hullabaloo about the 150th anniversary of the Emancipation Proclamation, signed by Lincoln on January 1, 1863, and the ensuing worship of St. Abe for freeing the slaves, it is a sure thing that the truth about the document will be lost.
To begin with, the Emancipation Proclamation did not free a single slave. It applied only to slaves in the states "in rebellion" – the Confederacy – where the Union had no power or authority, thus having about as much real effect as the famous (putative) papal bull against Halley's comet. And it did not apply to the Border states where there still was slavery (Delaware, Maryland, Kentucky, Missouri). In other words, as Secretary of State William Seward remarked ironically at the time, "We show our sympathy with slavery by emancipating slaves where we cannot reach them and holding them in bondage where we can set them free."
But then, it was not really intended to liberate anybody. It was, as Lincoln took care to spell out, a "military measure," issued under the president's authority as commander-in-chief, and its real purpose was to undermine the confederate army. This would be accomplished, Lincoln hoped, first by encouraging slaves to take over the plantations so that they would no longer be supplying foodstuffs for the soldiers, and second by causing plantation owners serving in the army to desert and rush home to protect their wives and children from the presumably dangerous freedmen.
Another possible effect, not spelled out and never specifically endorsed by Lincoln was, as Treasury Secretary Salmon Chase put it at one cabinet meeting on the Proclamation, that "universal emancipation" would set off "depredation and massacre" across the South. Such an uprising would surely be condemned by the greatest part of the North's population and public opinion abroad, and Lincoln sought to guard against this by saying in the document that "I hereby enjoin upon the people so declared to be free to abstain from all violence."
But the fact that he had to make such an injunction meant that such an outcome was surely held to be a possibility, one that would not be unwelcome to the Union.
The Proclamation had other glaring deficiencies as well that are best indicated by looking at...