Final answer:
The southern colonies would likely have seceded had slavery been banned during the Constitutional Convention, leading to potential fragmentation of the U.S. Economic dependencies on slavery in the South made the issue contentious, contrasting with gradual emancipation efforts in the North.
Step-by-step explanation:
If slavery had been banned outright, the southern colonies would have probably walked out of the convention and the U.S. would have eventually fragmented. The potential for a prohibition on laws attempting to ban the importation of enslaved people was a contentious issue during the framing of the new nation's Constitution.
The southern states, particularly South Carolina, had signaled that they would abandon the Constitutional Convention if the institution of slavery were threatened, leading the framers to avoid pressing for its outright abolition, despite the fact that many of them were personally against it.
Differing attitudes towards slavery had already been evident prior to the Constitution, with states in the North such as Pennsylvania, Vermont, Massachusetts, and New Hampshire taking steps to ban or curtail slavery. In contrast, southern states largely resisted these changes, and the number of slaves in the South grew substantially following the invention of the cotton gin.
Despite the dichotomy between North and South, some politicians and religious communities, including Quakers and individuals like James Otis, fiercely advocated for emancipation, drawing connections between the fight for independence and the moral imperative to end slavery. However, the Constitution ultimately protected slavery, aligning with many southerners' economic interests and social structures.