On June 26, 2015, the Supreme Court granted marriage equality to LGBT couples. Writing for the majority in Obergefell v. Hodges, then-justice Anthony Kennedy — the man whose retirement touched off the Brett Kavanaugh firestorm this summer — argued that these couples “ask for equal dignity in the eyes of the law. The Constitution grants them that right.” It was this opinion, more than anything else, that explains the strange liberal affection for Kennedy, who was mostly a reliable conservative vote for corporate power, voter suppression, and the contamination of our elections by unfettered wealth.

The reaction on the right to Obergefell was immediate, and fierce. A group of 60 conservative legal scholars publicly called for resistance to the Supreme Court’s ruling, and for “a broad and honest conversation on the means by which Americans may constitutionally resist and overturn” the ruling. Former GOP presidential candidate Mike Huckabee thundered, “I will not acquiesce to an imperial court any more than our Founders acquiesced to an imperial British monarch.” Ed Whelan, the conservative legal activist now famous for his role in popularizing the theory that Kavanaugh’s doppelgänger attempted to rape Christine Blasey Ford, wrote that “state laws defining marriage as the union of a man and a woman are valid and enforceable under the real Constitution.”

For a moment, it looked like the legitimacy of the court itself was being called into question. But what is legitimacy, this nebulous concept? It refers to the extent to which people in a hierarchical relationship regard the authority wielded over them as rightly exercised. If the government needed to use constant coercion to enforce its power, society would either quickly unravel or descend into hard authoritarianism.

If you want to know what legitimacy looks like in practice, consider what followed the initial reaction to Obergefell. Controversial Supreme Court decisions often require further enforcement and litigation, and while there are still sporadic, local efforts to resist the decision, such as those in Alabama, Obergefell was quickly accepted as law. Marriage equality, once an extraordinarily divisive issue, thereafter had the support of a 2–1 majority of the American people. Conservatives considered the issue wrongly decided, and plotted to overturn it, just as liberals dream of someday overturning Citizens United v. FEC. But they had no choice but to accept it.

There were several key factors working in favor of Obergefell’s legitimacy that will be very much missing from the next controversial Supreme Court decision. First, no one on the right or left, even opponents of the decision, could dispute that each seat on the court had been obtained justly, with popular consent. It was not until his second term, after he had won reelection with an actual popular vote majority, that George W. Bush made his first Supreme Court nomination. Second, none of the seats on the court had been obtained through disruptive parliamentary procedure, as is now the case with the seat held by Neil Gorsuch and the one that presumably will be filled by Kavanaugh.

When Republicans refused to hold confirmation hearings for Merrick Garland in 2016, they trashed two centuries of precedent holding that the president gets to fill vacancies on the Supreme Court when they open up. They were narrowly correct that the Constitution does not obligate the Senate to consider the president’s nominee. But the absurd explanation, advanced even today by Republicans who seem to have no understanding of the damage they’ve done, is that there had been a long-standing consensus not to do so in an election year.

There was not.

Many millions of Americans regard Neil Gorsuch in particular as illegitimate, his position on the court secured through a flagrant abuse of the Constitution’s spirit. To compound the crisis, both Gorsuch and Kavanaugh will have been approved by simple Senate majorities, after Mitch McConnell eliminated the filibuster for Supreme Court nominees in 2017. If confirmed, Kavanaugh will also serve under a cloud of suspicion after a rushed and incomplete FBI investigation that leaves multiple allegations of sexual assault unresolved. He may also have perjured himself during the course of recent, disturbingly partisan testimony before the Senate.

As if that were not enough, there remain fundamental questions about the legitimacy of Donald Trump’s election — not just the fact that he lost the popular vote decisively, but also the FBI’s crippling last-minute intervention against Hillary Clinton, and to what extent his campaign may have cooperated with a hostile foreign power to affect the results of the election.

This will create an extraordinarily combustible situation, as early as next summer. Conservative judicial reactionaries have spent nearly four decades in pursuit of a majority to overturn Roe v. Wade, and now they will have it. The court may endorse so-called fetal heartbeat laws that will effectively outlaw abortion as early as six weeks into a pregnancy. Iowa passed such a law this year. Roe, like marriage equality, also has 2–1 support in the general public.

This won’t be the first time the court has challenged a decisive majority of the American people with a tremendously unpopular opinion — many of the landmark decisions of the Warren Court, including those outlawing enforced segregation in public schools and requiring police officers to read a set of rights to anyone being arrested, were deeply unpopular at the time. Citizens United has always been hated. The key distinction will be that in the future, many millions of voters will not just dislike the rulings — they will consider the court majority issuing these unpopular opinions as ill-gotten, and consequently all of its decisions as tainted.

What will this crisis look like in practice? If Roe is overturned and abortion laws are left to the states, the crisis will predictably result in dozens of bitter legislative skirmishes from Harrisburg to Denver. But the Supreme Court could also endorse an even more fanatical stance by declaring an affirmative right to life for all fetuses past a certain point. They needn’t endorse the “personhood” movement that claims rights from the moment of conception to radically reduce choice in all states. After all, District of Columbia v. Heller didn’t leave gun laws to the states. Obergefell didn’t leave marriage laws to the states. How likely is it that conservatives, still livid over what they see as the creation of a new constitutional right in Obergefell and who have spent 40 years trying to gut Roe, will be content issuing a decision that results in abortion remaining legal in 20–30 states?

Imagine how this will look. Five men, two appointed by a corrupt popular vote loser whose impeachment could be imminent, will have gutted choice rights for all American women. Almost certainly, upward of 20 states and their governments (plus DC) will simply refuse to comply, instructing doctors and clinics to continue performing abortions according to the Roe framework and timeline. The president is on record saying women should be thrown in prison for having abortions if the practice is outlawed, and it’s not hard to imagine this federal government prosecuting women and doctors. Such a standoff could be violent, and would trigger a rolling crisis whose shape would be impossible to predict.

A different legitimacy crisis could follow a Democratic takeover of Congress and the presidency in 2020. If Clarence Thomas remains on the court, or is replaced by a younger hardliner in the interim, it is easy to imagine that the next two-term Democratic president will not get the chance to replace any of the conservative judges — they could spend eight years watching the court eviscerate every major progressive policy achievement, including Medicare for All. After all, many conservative judicial hardliners believe that the Social Security Act itself is unconstitutional, and this new hard-right court could obliterate New Deal–era reforms one by one, reinstituting what many of them call the “Constitution-in-Exile.”

Democrats could choose further escalation, as I have argued repeatedly, by expanding the Supreme Court and the federal judiciary. A court packed with progressives who reverse the 2008 decision overturning Washington, DC’s handgun ban, or find a constitutional right to equally funded public education, for instance, would likely find its decisions met with resistance in dozens of states, which might refuse to comply or even secede.

A second civil war remains remote — after all, most of the country, including the vast majority of the progressive left, is unarmed. But no one has really given serious thought to the idea that the United States might more peacefully come apart, a kind of velvet divorce that sees red and blue states disentangle themselves without recourse to violence. Democrats who shared the infamous “Jesusland/United States of Canada” map after the 2004 election might be more inclined to take radical action should the Supreme Court dismantle the New Deal social welfare apparatus or criminalize abortion. And conservatives might ask their states to walk away from the union rather than launch invasions of Chicago and San Francisco, should a progressive court cut into the prevailing interpretation of the Second Amendment.

That is one of the many reasons why the Kavanaugh nomination in particular is so fraught. There are many people (including me) who think that the theft of Garland’s seat broke the Supreme Court and set us on a path of court-packing and tit-for-tat escalation. But that estimation is probably not yet shared by the majority of Americans. If the process by which Kavanaugh is elevated is also seen as unjust and illegitimate, there may be no turning back. The United States is, after all, the only country in the world that combines lifetime judicial tenure with the highest court’s sweeping powers to set aside legislation, and there is no law that says this arrangement must continue indefinitely. It certainly isn’t expressly outlined in the Constitution.

That means there is one, and only one, consensus route out of this escalatory nightmare that results in the Supreme Court maintaining its current status in American life: The parties must agree on a broad compromise — a constitutional amendment that eliminates lifetime tenure for the Supreme Court, with service capped at 18 years. Presidents would have the right to nominate two justices per four-year term. This would instantly change the zero-sum character of SCOTUS appointments, because the court majority could conceivably flip back and forth once or even twice a decade. Justices might be incentivized to avoid more radical rulings that would be overturned by the very next court. And the country’s politics would no longer come to a boil every time a single 84-year-old justice has heart palpitations.

Wouldn’t that be nice?