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Americans are now debating the fate of memorials to the Confederacy—statues, flags, and names on Army bases, streets, schools, and college dormitories. A century and a half of propaganda has successfully obscured the nature of the Confederate cause and its bloody history, wrapping it in myth. But the Confederacy is not part of “our American heritage,” as President Donald Trump recently claimed, nor should it stand as a libertarian symbol of small government and resistance to federal tyranny. For the four years of its existence, until it was forced to surrender, the Confederate States of America was a pro-slavery nation at war against the United States. The C.S.A. was a big, centralized state, devoted to securing a society in which enslavement to white people was the permanent and inherited condition of all people of African descent.

The Confederates built an explicitly white-supremacist, pro-slavery, and antidemocratic nation-state, dedicated to the principle that all men are not created equal. Emboldened by what they saw as the failure of emancipation in other parts of the world, buoyed by the new science of race, and convinced that the American vision of the people had been terribly betrayed, they sought the kind of future for human slavery and conservative republican government that was no longer possible within the United States. This is the cause that the statues honor.

The decision of slaveholding states to secede, to separate from the United States, was the culmination of a 30-year effort to protect the right to hold property in persons—the institution of slavery. It came in response to Abraham Lincoln’s election, the first of an openly antislavery candidate and party. From December 1860 to April 1861, seven states left the Union, led by South Carolina; four more did so after the war began, in April 1861, while four slaveholding states remained loyal. The architects of secession knew that there was no recognized constitutional right to secede and that they risked war. As one Alabama opponent put it, “No liquid but blood has ever filled the baptismal font of nations.” The seceded states immediately went on a war footing, seizing federal forts and arsenals and launching massive arms-buying campaigns in the U.S. and Europe.

Nascent Confederates were candid about their motives; indeed, they trumpeted them to the world. Most states wrote justifications of their decision to rebel, as Jefferson had in the Declaration of Independence. Mississippi’s, called the “Declaration of Immediate Causes,” said bluntly that the state’s “position is thoroughly identified with the institution of slavery.” The North, it said, was advocating “negro equality, socially and politically,” leaving Mississippi no choice but to “submit to degradation, and to the loss of property worth four billions of money or … secede from the Union.”

In late February 1861, in Montgomery, Alabama, the seven breakaway states formed the C.S.A.; swore in a president, Jefferson Davis; and wrote a constitution. That constitution aimed to perfect the original by dispensing with all the issues about slavery and representation that had plagued political life in the former U.S. The document recognized the constituent states as sovereign entities (though it did not confer on them the right to secede, confirming Lincoln’s point that no government ever provides for its own dissolution). It put the country under God and mandated a one-term presidency, of six years. It purged the original of euphemisms, using the term slaves instead of other persons in its three-fifths and fugitive-slave clauses. It bound the Congress and territorial governments to recognize and protect “the institution of negro slavery.” But the centerpiece of the Confederate constitution—the words that upend any attempt to cast it simply as a copy of the original—was a wholly new clause that prohibited the government from ever changing the law of slavery: “No … law denying or impairing the right of property in negro slaves shall be passed.” It also moved to limit democracy by explicitly confining the right to vote to white men. Confederates wrote themselves a pro-slavery constitution for a pro-slavery state.

Shortly after this constitution was written, Alexander Stephens, the vice president of the C.S.A., offered a political manifesto for the slaveholders’ new republic. Training his sights on the eight upper-South states that were still refusing to secede, he offered a blunt assessment of the difference between the old Union and the new. The original American Union “rested upon the assumption of the equality of the races,” he explained. But “our new government is founded upon exactly the opposite ideas: its foundations are laid, its cornerstone rests, upon the great truth that the negro is not equal to the white man; that slavery is his natural … condition. This, our new government, is the first, in the history of the world, based on this great … truth.” A statue of Alexander Stephens now stands in the U.S. Capitol; it is one of a group that includes Jefferson Davis and Robert E. Lee, targeted for removal.

The war brought a terrible reckoning for the Confederate States of America, subjecting it to the military test of the Union armies and the political judgment of its own people. The C.S.A. was a nation built on a slim foundation of democratic consent: Of its total population of 9 million, only about 1.5 million were white men of voting and military age; the rest—white women and the enslaved—formed the vast ranks of the politically dispossessed. Political consent, and popular support for the war effort, were accordingly shallow.

The C.S.A. was a fraction of the size of its enemy. The Union had 10 times its manufacturing capacity, and its population of 22 million dwarfed that of the Confederacy. It quickly became clear what such imbalances meant: The Confederacy had to exert unsupportable demands on its population, and to build up a powerful central-state government to do what the private sector could not.

After one year of war, the Davis administration was forced to adopt the first conscription act in American history. Because enslaved men were not available for military service, it was forced to mobilize a far higher proportion of white men. By the end of the war, a staggering 75 to 85 percent of white men ages 15 to 55 had served. Combined with the exemptions the government was forced to make for slaveholders, conscription quickly gave rise to charges that it was a “rich man’s war, poor man’s fight.”

The C.S.A.’s level of military mobilization was unsupportable in an agrarian society. By 1863, the government faced a starvation crisis and a wave of food riots organized by white soldiers’ wives protesting the government’s military policies. The Confederacy adopted a series of highly intrusive taxes, labor regulations, and impressment policies. Nobody loved Jefferson Davis when they had to live under his government. The modern embrace of the C.S.A. as a symbol of states’-rights government is particularly ironic in light of its history.

The Confederate States of America went to war against the United States to secure the enslavement of people of African descent into the indefinite future. Confederate leaders claimed that slavery would prove a strength in wartime, but it did not. To the contrary, enslaved men, women, and children seized the opportunity the war offered to make their own history, turning the war to save the Union into a war of liberation. They made their military value abundantly clear. One Confederate officer complained that the South was waging war with the Union army in front and “an insurrection in the rear,” advising the leadership to try to win the loyalty and military service of the enslaved with promises of freedom. The Davis administration would belatedly make some abortive efforts to recruit enslaved men to save the slaveholders’ republic, one telling indication of how incoherent the national project had become. But it was the U.S. government and armies that won enslaved peoples’ allegiance and service—securing, in return, the Emancipation Proclamation, the Thirteenth Amendment, and the defeat of the Confederacy.

The Confederacy went to war against the United States to protect slavery and instead brought about its total and immediate abolition. By April 1865, the C.S.A. was in ruins, its armies destroyed. The cost in human life was devastating: at least 620,000 dead—360,000 from the U.S. and 258,000 from the C.S.A. On April 9, at Appomattox Court House, Virginia, U.S. General Ulysses S. Grant accepted the unconditional surrender of General Robert E. Lee and his Army of Northern Virginia.

Whatever way you look at it, it is impossible to turn this history and its leading figures into a part of American heritage. Founded in an act of treason against the government its leaders had sworn to protect and serve, the Confederate States of America and its white-supremacist government waged a four-year war against the United States of America and the principles Americans value most highly.

This is the cause that Confederate statues commemorate. This is why white supremacists arrive armed to prevent their removal, as they did in Charlottesville, Virginia, in 2017. And it is why they are a target of Black Lives Matter protesters in their campaign for racial justice and a crucial part of the conversation about the legacy of slavery in American life.

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