In the life of President Abraham Lincoln, there are any number of dramatic and momentous moments. For the fate of the nation, there is perhaps none more consequential than the issuance of the Emancipation Proclamation on January 1, 1863. That document provided “that all persons held as slaves” within the rebellious states “are, and henceforward shall be free.” The proclamation did not complete the job of ending slavery. It applied, as written, only to slaves held in states, which were not then under federal control, and therefore its immediate practical impact was limited. Still, it was monumental in its impact....