The Founding Fathers agreed in the US Constitution to permit a ban on the importation of slaves to the United States as soon as January 1, 1808. In 1807, Congress debated and passed a bill banning American participation in the Atlantic slave trade under the leadership of Massachusetts representative, Barnabus...
Bidwell, President Jefferson's spokesman in the US House of Representatives. Most state governments by this time had also restricted or banned the trade.
Beyond this, as events were to show, there were significant political, economic, and social impediments to ending slavery. Sectional interests were already clear. The enlightened Harvard- and Yale-educated New England gentry wanted to end slavery, which they viewed as a moral stain on the new republic. The Northern economy was diversified and far less dependent on slave labor. They were opposed in the North by urban working-class immigrants in New York and Boston who feared that increasing the supply of unskilled labor would drive down their wages.
In the agricultural South, cotton, indigo, rice, and tobacco were labor-intensive but potentially highly profitable cash crops on which the current social and economic order depended. Slavery was considered an economic necessity to maintain this order. Because the participation of the South had been a sine qua non of American independence, the South believed that the new republic owed its independent existence to their aid during the revolution and that any attempt to destroy their economic system meant a betrayal of an unspoken agreement dating from the American Revolution.
This gridlock was exacerbated by western expansion. The South wanted to extend slavery westward, while the North was just as committed to preventing any such expansion. The South could have gradually diversified its economy and emancipated its slaves and adapted them to free labor, but the voices of reason in the North and the South were drowned out by the more numerous hardliners in both regions.
This is one of the great failures of the American political leadership, as practically every one of the many other slave-based economies around the world was able to peacefully transition to free labor without a costly and bloody civil war in the same period. That being said, it is perhaps unrealistic to expect the Founding Fathers themselves to have accomplished this transition completely given the political, economic, and social impediments that they faced, and especially given that their personal influence was in decline or nonexistent in the democratic enthusiasm of the Jacksonian era. They had perhaps done as much as they could reasonably be expected to do by ending America's participation in the Atlantic slave trade given the economic and institutional legacy of the British colonial system to which they were heirs but not the authors.