The 14th Amendment states, “All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the state wherein they reside.” Additionally, the amendment builds on the tradition of federalism by asserting that “no state shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any state deprive any person of life, liberty or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.”

That language applies to every person born on U.S. soil, with limited exceptions for the children of foreign diplomats and children of Indigenous nations, which have their own sovereignty.

Birthright citizenship “was meant for the babies of slaves; it was not meant for people trying to scam the system and come into the country on a vacation,” Mr. Trump said at a news conference last month in which he explained his interpretation of the 14th Amendment and the reasoning behind the country’s birthright citizenship case, apparently enlisting a magical line-item veto to disappear that nettlesome language known as the equal protection clause. “It was the exact same date, the end of the Civil War, and it was meant for the babies of slaves, and it was so clean and so obvious, but this lets us go there and finally win that case.”

It was not. It did not.

In 2017, nine months into Mr. Trump’s first term as president, the writer Ta-Nehisi Coates presented an argument that remains a skeleton key to how we arrived at our present discontent: Mr. Trump is best understood as the nation’s first white president. His election was a repudiation of Mr. Obama’s presidency. Mr. Trump’s path to the White House started with his notorious birther crusade against Mr. Obama.

Mr. Trump’s crusade was a specious and racist effort to delegitimize the election of the nation’s first Black president. “For Trump,” Mr. Coates wrote, “it almost seems that the fact of Obama, the fact of a Black president, insulted him personally.” Having witnessed how Mr. Trump has wielded power during the first six months of his second term, swiftly moving to institute this MAGA version of Juan Crow — now with a supersized ICE budget that rivals what some nations spend on their entire militaries — I think we can safely dispense with the word “almost.”

It’s instructive to look at a previous moment when white supremacy was welcome at the White House. In 1915, President Woodrow Wilson hosted a special screening of D.W. Griffith’s “The Birth of a Nation.” Less than 50 years after the ratification of the 15th Amendment (prohibiting the denial of the vote based on race, color or having been enslaved), Griffith’s blockbuster cinematic argument for the necessity of Jim Crow was released. The film (based on the 1905 novel “The Clansman,” written by Thomas Dixon Jr., a classmate and friend of Wilson) is chiefly notorious for promulgating a fiction of Black men as marauding rapists obsessed with gorging themselves upon the carnal altars of white virginity. In the film, a white victim, Flora Cameron (played by Mae Marsh), jumps off a cliff to her death to avoid marrying, and thus consummating with, a freedman and veteran Union captain named Gus (portrayed by Walter Long, in blackface). That is only one of the film’s expressions of displeasure with the changes Reconstruction brought about.

Griffith’s film spoke to the reactionary, bristling rage of white people witnessing Black men serving in state legislatures and the U.S. Congress, exercising the right to vote and holding positions of local authority. Newly enfranchised Black men throughout the South voted in the 1868 election, helping make Ulysses S. Grant president. For those who needed the false supremacy of whiteness to be real, this was unconscionable. Offscreen, that rage famously resulted in the only successful coup d’état on American soil: the Wilmington Race Massacre of 1898.

For Mr. Trump, returning the country to greatness involves stopping an invasion that is about as real as Griffith’s projections. When Kristi Noem, the Department of Homeland Security secretary, visited the Salvadoran prison known as the Terrorism Confinement Center, or CECOT, over which the president of El Salvador, Nayib Bukele, presides, she shared images seemingly engineered to light up the same synapses that brought Griffith so much fame and praise. The policy works hand in hand with the spectacles, much like lynchings, that followed trials in Jim Crow kangaroo courts. The Trump administration’s elastic incursion into habeas corpus and due process rights wouldn’t be complete without intimidating images burnishing its will and ability to abuse with impunity.

Griffith’s order-restoring Ku Klux Klan night riders bring to mind some aspects of today’s professionalized immigration enforcement. ICE officers are permitted to mask their faces, to engage in profiling as they snatch people off the street and hustle them into unmarked cars, disappear them into overcrowded, filthy oblivions, execute cruel and inhumane family separations and trample on the rights of U.S. citizens. Desperate ICE detainees have used their bodies to form SOS signals and, more recently, to break through a wall and escape a facility in New Jersey.

The Trump administration has repeatedly obstructed elected officials from conducting basic oversight. There is a pattern of impunity and contempt in the way the Department of Homeland Security stonewalled Mayor Ras Baraka of Newark, Representatives LaMonica McIver and Bonnie Watson Coleman of New Jersey, Representatives Adriano Espaillat and Nydia Velázquez of New York and Representatives Maxine Waters, Jimmy Gomez and Norma Torres of California when they attempted to gain access to federal facilities, as is their right and duty.

Perhaps because frequency and repetition confer dulling effects, Americans seem to have become numb to the dangers of the ongoing shameless, targeted, personal and bigoted diminution of the capabilities, achievements and authority of women and people of color who occupy government. As the transgressions grow bigger and bolder, the effects become normalized, entrenched. We are passively becoming witnesses to near-daily insults, the cumulative effect of which is to make them appear as if they were deserved.

Left unchecked, the currents of autocratic abuse can swell in a flash, allowing the floodwaters of white supremacy to sweep away democracy in America — again.