The Constitution’s slavery clauses were compromises, efforts to find a middle ground between the institution’s critics and defenders. Taken together, however, they embedded slavery more deeply than ever in American life and politics. The slave trade clause allowed a commerce condemned by civilized society—one that had been suspended during the War of Independence—to continue until 1808. On January 1, 1808, the first day that Congress was allowed under the Constitution, it prohibited the further importation of slaves. But in the interim, partly to replace slaves who had escaped to the British and partly to provide labor for the expansion of slavery to fertile land away from the coast, some 170,000 Africans were brought to the new nation as slaves. South Carolina and Georgia imported 100,000. This number represented more than one-quarter of all the slaves brought to mainland North America after 1700.

The fugitive slave clause accorded slave laws “extraterritoriality”—that is, the condition of bondage remained attached to a person even if he or she escaped to a state where slavery had been abolished. John Jay, while serving in Spain on a diplomatic mission, once wrote of how he missed the “free air” of America. Jay was probably unaware of the phrase’s full implications. In the famous Somerset case of 1772, the lawyer for a West Indian slave brought to Britain had obtained his client’s freedom by invoking the memorable words, “the air of England is too pure for a slave to breathe” (that is, the moment any person sets foot on British soil, he or she becomes free). Yet the new federal Constitution required all the states, North and South, to recognize and help police the institution of slavery. For slaves, there was no “free air” in America.

The Constitution gave the national government no power to interfere with slavery in the states. And the three-fifths clause allowed the white South to exercise far greater power in national affairs than the size of its free population warranted. The clause greatly enhanced the number of southern votes in the House of Representatives and therefore in the electoral college (where, as noted above, the number of electors for each state was determined by adding together its number of senators and representatives). Of the first sixteen presidential elections, between 1788 and 1848, all but four placed a southern slaveholder in the White House.

The Signing of the Constitution, by mid-nineteenth-century American artist Thomas Pritchard Rossiter, depicts the conclusion of the Constitutional Convention 0/1787. Among the founding fathers depicted are James Wilson, signing the document at the table in the center, and George Washington, presiding from the dais with an image of the sun behind him.

The preamble to the Constitution, as printed in a Pennsylvania newspaper two days after the Constitutional Convention adjourned.

Even the initial failure to include a Bill of Rights resulted, in part, from the presence of slavery. As South Carolina delegate Charles C. Pinckney explained, “such bills generally begin with declaring that all men are by nature born free,” a declaration that would come “with a very bad grace, when a large part of our property consists in men who are actually born slaves.”

But some slaveholders detected a potential threat buried in the Constitution. Patrick Henry, who condemned slavery but feared abolition, warned that, in time of war, the new government might take steps to arm and liberate the slaves. “May Congress not say,” he asked, “that every black man must fight? Did we not see a little of this [in the] last war?” What Henry could not anticipate was that the war that eventually destroyed slavery would be launched by the South itself to protect the institution.

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