Well, let's see. Great Britain did it within 6-7 years, no bloodshed, Mexico by 1829, and France and her colonies by the early 1850s. Guess what? No bloodshed either. To quote from DiLorenzo's book
Dozens of countries, including the possessions of the British, French, and Spanish empires ended slavery peacefully during the late eighteenth and nineteenth centuries. ONLY in the United StateS was warfare associated with emancipation
That's amazing isn't it. Within 6 years in Great Britain AND colonies without any bloodshed. Yet lincoln uses it as an excuse to put the nation $600 million+ in debt, spends 4 years, has the blood of 300,000 of his own citizens and 300,000 citizens of another nation on his hands, and achieves the exact same thing. Surely you would imagine that lincoln was not ignorant to what had occurred a scant decade earlier in the world. Of course it was over slavery < /sarcasm>
So what would you (or DiLorenzo) advise Lincoln to do? Send a note to the Confederates saying he wanted to end slavery in America without bloodshed like the British, et. al did and expect that to convince the fire-eaters down South who put a value of $3,000,000,000 on their slaves?
The Brits paid slaveholders about £200 per slave, but they could get away that cheaply because the British slaveholders were few far between -- spread out in Colonies throughout the world. The $3 billion value placed on the slaves by the Confederates is about equivalent to $57 billion in current dollars, but as a percentage of the GDP it would be about $3 trillion in current dollars. How far do you think Lincoln would have gotten in Congress with a proposal to pay the slaveholders that kind of money?