Nikolas Bowie is assistant professor at Harvard Law School. A historian, he teaches and writes about federal and state constitutional law.

Every January, I write a letter to my incoming law students to get them excited about learning constitutional law. That letter was not easy to write this time.

The past few years have shaken my faith in the Constitution. Like many law professors, I once confidently predicted that the Constitution would never permit a president to ban Muslim travelers or put toddlers in cages. I also thought the document prohibited police officers from inflicting excessive force on Black bodies — despite everything I witnessed to the contrary.

Still, as recently as two months ago, I thought there was consensus around some interpretations — for instance, that nothing in the Constitution permitted anyone to single-handedly overturn the results of a presidential election. The white nationalists who stormed the Capitol to reject that interpretation left me questioning how long the document will survive.

Yet as surprised as I was, I had to share a difficult truth with my students: This has all been a continuation of — not an aberration from — America’s constitutional tradition.

A striking photo from the insurrection depicts a man holding a Confederate flag outside the Senate chamber. Behind him, on permanent display, is a portrait of John C. Calhoun. Calhoun roamed the Capitol shortly after its construction by enslaved workers. He boldly protected the system of racialized violence that oppressed these workers — as did the Constitution.

One of those protections was the method the Constitution prescribed for presidential elections. It allowed Calhoun’s state of South Carolina to count three-fifths of its enslaved residents as if they supported the state’s choice for president. As the Constitution authorized, the legislature itself allocated the state’s electoral votes, sent Calhoun to the Senate and malapportioned its own seats to ensure the political domination of wealthy slaveowners.

Similar protections of racial subordination pervade the Constitution. The taxing clause was structured to prevent the federal taxation of enslaved property. The commerce clause was interpreted to prevent Congress from regulating commerce in enslaved people. The fugitive slave clause authorized agents to raid and deport northern Black people into slave states.

The Civil War brought with it a decade of constitutional renewal. The 13th, 14th and 15th amendments abolished slavery, guaranteed the equal citizenship of Black people and enfranchised Black men. Federal civil rights laws permitted multiracial democracy to exist in this country for the first time.

But the moment was fleeting. Terrorists clad in white hoods and red shirts lynched Black voters. The Supreme Court declared that Congress had no power to stop this violence. The court warned that Congress was “running the slavery argument into the ground” when it passed anti-discrimination laws, and it was time for Black people to “cease to be the special favorite of the laws.” White Americans gleefully responded by inaugurating a system of racial apartheid.

The Supreme Court condoned this system, interpreting the 14th Amendment to protect corporations but not people of color; to permit disenfranchisement but not redistribution; to allow lynch mobs but not labor protections. Only after the Great Depression did the court reevaluate its precedents and permit Congress to reshape the constitutional order the court had sustained. Demonstrators spent the next century marching to resurrect the nation’s fragile commitment to multiracial democracy. Yet they encountered massive resistance, persisting to this day, from Confederate-flag-waving opponents.

I wrote all this to my students to explain why this past year’s violence reads like the unexpected page of a familiar story.

Yet I also wrote that this story need not end in tragedy. The Constitution has done far more than tolerate profound injustice. The clauses that once permitted the exclusion of Chinese laborers forged a country whose liberties attracted immigrants from around the world. The articles that sanctioned the dispossession of Native tribes have evolved to stand for democratic self-rule. The same words that invalidated minimum-wage laws now guarantee reproductive freedom, marriage equality and religious liberty. An antiquated document that enabled so much that was wrong has also protected so much that is right.

What I want my students to learn is that the difference between a just and unjust interpretation of the Constitution — between a peaceful transfer of power and an armed insurrection — is not an objective question of linguistics. It is a subjective matter of moral principle. What has made the Constitution good is not courts reflecting back the flawed principles of their own societies. It has been rising generations like my students who demand that new principles are necessary for the Constitution to live up to its own words and “establish Justice.”

I told them, in short, that they don’t need to like how the Constitution has been interpreted. But they do need to understand how it should be interpreted. The Constitution provides the vocabulary by which this country debates what is just.

As the Rev. Martin Luther King Jr. observed at the beginning of the Montgomery bus boycott in 1955, “If we are wrong, the Constitution of the United States is wrong.” He did not think the Constitution was wrong. Neither do I.

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