The character of the Civil War could not possibly have been the same after the President issued the Emancipation Proclamation as it had been before January 1, 1863. During the first twenty months of the war, no one had been more careful than Lincoln himself to define the war merely as one to save the Union. He did this not only because such a definition greatly simplified the struggle and kept the border states fairly loyal, but also because he deeply felt that this was the only legitimate basis for prosecuting the war. When, therefore, he told Horace Greeley that if he could save the Union without freeing a single slave he made the clearest possible statement of his fundamental position. And he was holding to this position despite the fact that he had written the first draft of the Emancipation Proclamation at least six weeks before he wrote his reply to Greeley’s famous “Prayer of Twenty Millions.”
Lincoln saw no contradiction between the contents of his reply to Greeley and the contents of the Emancipation Proclamation. For he had come to the conclusion that in order to save the Union he must emancipate some of the slaves. His critics were correct in suggesting that the Proclamation was a rather frantic measure, an act of last resort.