Is America a democracy? The term implies an equality of rights and dignity among citizens, a collective and uniform right of individuals to participate in self-government and to shape the laws that rule them. In that sense, the answer is no: though it has been a republic since its founding, America has only rarely been a true democracy, one where all citizens have the full right to vote and to have that vote counted.

Political scientists such as the University of Notre Dame’s Christine Wolbrecht have argued that America wasn’t really a democracy, not in the meaningful sense of the term, until the passage of the Voting Rights Act, the law that formed the signature achievement of the civil rights movement and sought to end racial barriers to voting across the south when it was passed in 1965. If you accept that premise, you could say that the era of American democracy officially ended on Wednesday, when the supreme court finished its project of dismantling the VRA in its 6-3 decision in Louisiana v Callais. Whatever this country has become now, “democracy” does not describe it.

The decision, authored by Samuel Alito and joined by the Republican appointees Clarence Thomas, John Roberts, Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett, completes an effort that the court began in 2013’s Shelby County v Holder, in which the justices struck down the VRA’s section 5. Section 5 had required federal oversight of voting laws and districts adopted by states with a history of racial discrimination in voting; its absence has already led to greater difficulty for minority voters in Republican-controlled states to elect the representatives of their choice – usually Democrats.

In that 2013 decision – and in subsequent rulings that further weakened the Voting Rights Act over the intervening years – the court had claimed that section 5’s protections were no longer necessary to ensure minorities’ equal access to the franchise, because the law’s section 2, requiring that no state adopt a voting practice or district map that discriminated on the basis of race, was still standing. In his Callais opinion, seeking to preserve the pretext that the court was merely altering the application of the VRA’s section 2, rather than eliminating it entirely, Alito suggested that he was merely creating a new set of tests for the law. Do not believe this: section 2 is now effectively moot. The court has drawn new standards for plaintiffs to establish claims of illegal racial discrimination in voting that virtually no case will be able to meet. The Voting Right Act is dead.

It is not an exaggeration to say that the changes that will result will likely represent the greatest withdrawal of voting power from Black Americans since the end of Reconstruction and the establishment of Jim Crow. It is difficult to say how many seats Democrats will lose in the coming Republican redistricting bonanza that the court’s decision will allow. A New York Times analysis found that the ruling would endanger about a dozen Democratic-leaning seats across the American south. A report by Fair Fight Action, the voting rights group led by the Georgia Democratic activist Stacey Abrams, says that Republicans could pick up as many as 27 seats. Some of these will be snatched up as early as the November 2026 primaries, with Republican-controlled states scrambling to eliminate majority-minority districts that had been previously mandated by what remained of the VRA. Others will shift to the Republicans over the course of the coming years, as statehouses redistrict ahead of the 2027 special elections and the 2028 cycle.

That’s because according to the court, it is now acceptable for voting districts to have racially discriminatory impacts so long as they cannot be proved to have racially discriminatory intent. Alito’s opinion overturns the 1982 reauthorization of the Voting Rights Act, which specifically said that voting district maps needed to be drawn in a way that preserved the equitable representation of racial minorities – and that mere discriminatory impact was sufficient to render maps illegal, with no evidence of discriminatory intent required. Discarding congressional intent entirely, Alito claims that this provision is itself unconstitutional, because in order to ensure equal representation for Black voters, redistricting bodies have to consider race. This, the court contended, constitutes discrimination against non-Black voters. Instead, a facially race-neutral – but in effect racially discriminatory – new regime has been imposed.

Now, under the court’s new regime, de facto racial gerrymandering will be blessed, under the new standard established by the court’s Republican justices, so long as it is presented with the fig leaf of having merely partisan intent. That racial gerrymanders can be disguised as partisan gerrymanders, because in many states there are deep partisan divisions between voters of different races, is the reality that allows this bad-faith pretext to be passed off to the American public in a vulgar display of cynical faux-neutrality. It is transparent, disingenuous sophistry to pretend that racial gerrymanders can be hidden behind mere partisanship, just as it is transparent, disingenuous sophistry to pretend that the 14th amendment, which was enacted in the aftermath of slavery, and the Voting Rights Act, which was enacted to end Jim Crow, were meant to prohibit any state acknowledgement of race at all, rather than to end the oppression of Black Americans by white ones. The court’s opinion makes these claims because they are transparent, disingenuous people, and because they think that the American people are stupid.

But reality pays little heed to such word games: the reality is, now, that Black voters in the American south will be procedurally barred from electing candidates of their preference, and that Republicans will reap the rewards. Longtime court observers note that the elimination of the VRA has been a decades-long dream of the chief justice, John Roberts, a George W Bush appointee, who had written of his disdain for the law and his desire to see it eliminated as early as the 1980s, during his time in the White House counsel’s office in the Reagan administration. Roberts has often presented himself as an instutituonalist, more reasonable and less vulgar than colleagues to his right, like Alito or Thomas. But the elimination of the Voting Rights Act will be his true legacy, and it is this that he should be remembered for: a hostility to multiracial democracy that he valued more than his own intellectual honesty, more than his dignity, and much, much more than the integrity of his institution – a hated and discredited court which now lies in ruins at his feet.

• Moira Donegan is a Guardian US columnist