Historical mythology treats it as one of America’s shining moments. Amid a searing civil war, the saintly president freed America’s slaves with the stroke of a pen, and a moving commitment to equality, which went into effect one hundred fifty years ago. In fact, Abraham Lincoln’s Emancipation Proclamation of September 22, 1862, slated to go into effect January 1, 1863, is more prose than poetry, more a cautious state paper than a sweeping declaration. Historian Richard Hofstadter scoffed that it had “all the moral grandeur of a bill of lading.” Indeed, this limited document only freed “all persons held as slaves within any State or designated part of a State, the people whereof shall then be in rebellion against the United States.” There is, however, a deeper lesson here. Much of Abraham Lincoln’s greatness -- and his effectiveness -- stemmed from such caution. The remaining slaves in the Union were freed eventually and -- thanks to Lincoln -- inevitably. But even during America’s great Civil War, Abraham Lincoln remained rooted in America’s centrist political culture, preferring an incremental pragmatism to zealous extremism.