By 1860? No. By 1900? Maybe/probably. Brazil was the last in the West to do abolish it and that was in 1888 and without a war.
No, by 1900 certainly not.
By 2017, maybe, but the mind shudders to think how history would have been different.
The key point to remember here is that in 1860 the US South was the strongest bastion of slavery in the world.
Had it defeated the Union and remained independent it would have served as a beacon of slavery against the forces of abolition.
Confederates dreamed of expansion into the Caribbean and Central America as the most natural realms for slavery's future.
Had they done so they would have brought heart & encouragement, aid & comfort to other slaveholders worldwide, in Brazil, for example.
And national-racial supremacists in places like Central Europe and Eastern Asia would have found natural allies in the Confederate Slave Power.
The tide of history would have turned and we would see a very different world today, whether Confederates had ever officially abolished slavery or simply changed the definitions of a few words.