Question

Why did slavery continue after the Revolution?

Answer 1

Because the Revolution and its ideas and ideals were not nearly as popular as we imagine they were, looking back. In fact there was a great deal of loyalist sentiment, and even moer of reluctance to rock the boat, run the risk of war and ruin, and cut the country off from the benefits -- and they were many! -- of association with what was then the world's superpower, Great Britain.

Those who led the Revolution could only keep enough support to keep the Revolution going by focussing narrowly on issues that moved everybody in the same direction, e.g. hostility towards the encroachment of arbitrary royal power from England. (You'll note that the Declaration is actually silent on the crimes of England and the English, dwelling only on George III. You get the impression that if the English had thrown out George III and replaced him with a more accomodating monarch, the Patriots would have said oh well that's OK then, and retracted the Declaration and foregone independence. That's because Jefferson needed to avoid pissing off his countrymen who LIKED England, and the English, and being part of the English system.)

Had the Revolutionaries insisted that the Revolution also meant the abolition of slavery (and certainly many, if not most of them felt it should), they would have divided their support fatally. Enough of the South would have been alienated to fatally weaken the support of the Revolution there, and the whole enterprise would have failed.

The Founders chose to narrow their goals to the establishment of a self-governing republic, and tackle the problem of slavery later. Was that the right choice? Maybe, maybe not. Other parts of the British Empire abolished slavery first, and then moved towards independence later, and did not experience the pernicious effects of slavery. But then, no other part of the British Empire dependend as much, economically speaking, upon slavery, so that may not mean much.