There were many reasons why this composite nation unraveled in the mid-19th century—but one in particular exposed the idea of the “United” States as a lie. This was the fact that even before the founding, enslaved people repeatedly risked their lives to flee their masters in search of freedom. The Founding Fathers knew the problem firsthand. Many of them were slaveholders themselves, including Thomas Jefferson and George Washington, whose own slaves periodically ran away. And so, in Article IV, Section 2, Clause 3 of the Constitution, which came to be known as the Fugitive Slave Clause, they tried to solve the problem. That clause declared that “no person held to service or labor in one state” could escape from coerced labor by fleeing from a state where slavery was legal to a state where it was illegal.
The constitutional principle was clear, but it proved to be unenforceable. Over the first half of the 19th century, as enslaved men and women ran from slavery to freedom, the federal government remained too weak to do much to stop them. By the second quarter of the century, some of the fugitives—the most famous was Frederick Douglass—were telling their stories with the help of white abolitionist editors in speeches and memoirs that ripped open the screen behind which America tried to conceal the reality that a nation putatively based on the principle of human equality was actually a prison house in which millions of Americans had virtually no rights at all. By awakening Northerners to this fact, and by enraging Southerners who demanded the return of their “absconded” property, they pushed the nation toward confronting the truth that America was really two nations, not one.
Politicians of all parties pretended otherwise. From the mid-1830s to the mid-1840s, hoping to restore “tranquility to the public mind,” the House of Representatives observed what became known as the Gag Rule, which required that any petition demanding action against slavery must be tabled immediately upon receipt without debate. Yet the truth about the divided state of the union could not be squelched. As the nation expanded westward, the border between slave states and free states became longer and more porous, and slaves continued to cross it.
In 1846, with the outbreak of the Mexican War, the final reckoning was set in motion. With strong but not universal support in the South, and against strong but not universal resistance in the North, both halves of the United States joined to wage a war of conquest. By the time the fighting ended two years later, the United States had seized a huge swath of land stretching from Texas to California, nearly equal in size to one-third of our present-day nation. This immense expansion of territory under control of the federal government brought back the old question of compromise between slavery and freedom in a new form and with more urgency than ever. Would slavery be confined to states where it already existed, or would it be allowed to spread into the new territories, which would eventually become states? A growing number of white Northerners insisted on the former. White Southerners almost universally demanded the latter. The fragile political truce that had held the United States together was coming apart.
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