In the run-up to Donald Trump’s election in 2016, the Republican nominee was short of detailed proposals. His campaign had been built around cuckoo-in-the-nest opportunism and a catchphrase crudely appropriated from Reagan’s victory in 1980. David Frum reduced the madness to its memorable minimum when he wrote: “If you voted for Donald Trump, you’d get Donald Trump, in all his Trumpery and Trumpiness.”

Yet there was at least one solid piece of business Trump could promise to get done. He would take the advice of the Federalist Society when it came to picking his nominees for the Supreme Court. The society, founded in 1982, had become a cornerstone of American conservatism, advocating an approach to the law rooted in the text of the Constitution. They had already vetted judges from across the land, producing a list of suitable “originalists”. Using their list didn’t just provide less work for the incoming administration. It showed that the Trump White House would be committed to judicial conservatism.

Many mock Democrats for their purity tests but, in the form of the Federalist Society, Republicans have their own. Conformity is almost guaranteed. Yet into a political landscape usually flatter than North Dakota, there came some rocky relief on Monday when the Supreme Court of the United States issued a surprising judgement. In the case of Bostock v. Clayton County, they voted by six votes to three in favour of extending the anti-discrimination principles of Civil Rights laws to protect gay and transsexual employees in the workplace. This was a big win for the LGBT community in America, but if you held up your ear to social media, you could also hear the squeal of brakes on countless flatbed trucks as they came to a juddering halt. Trump supporters were not happy with what they’d just heard. It was not how it was meant to go.

As far as they were concerned, the worst outcome should only amount to a hollow victory for the liberals. Justices Thomas, Alito, Gorsuch, and Kavanaugh would always fight for conservative values; Ginsburg, Breyer, Sotomayor and Kagan would mount a defence reliant on the precarious swing vote of the Chief Justice. John Roberts has always been considered the weakest link on the conservative bench and accounts for the general sense that Trump’s work is far from over. The President has yet to stack the Supreme Court in his favour and thereby ensure the eventual overturning of Roe vs Wade, the 1973 decision that currently protects a woman’s right to an abortion in all states.

This is the metanarrative that touches upon everything important in America at the moment and has turned Justice Ruth Bader Ginsburg into a cultural icon, every one of her health scares into potential turning points of history.

If 5-4 might have been expected and something of a placeholder for future conservative victories, 6-3 makes this hugely significant in the history of American civil rights. Yet it was also the moment when Neil Gorsuch declared his independence from the president who appointed him; a timely reminder, too, that there is not just one type of “conservatism” in America.

In recent years, the apparent successor to Antonin Scalia has become something of a forgotten man on the list of characters supporting the Donald Trump show. Brett Kavanaugh’s confirmation was one of the front row events of this presidency. It read like “Horatio Alger: The Forgotten Days”; the story of an American Dream scrawled drunkenly over a frat-house wall. Kavanaugh became emblematic of a court that was supposedly rigged to produce conservative results. Yet it’s easy to overlook that Kavanaugh was Trump’s second selection for the Supreme Court. Before him came the solidly conservative Gorsuch, with no skeletons in his cupboard, and with as easy a path to nomination as Kavanaugh’s was fraught.

Crucially, Gorsuch has also proved to be no Trumpian. In his book of essays, “A Republic, If You Can Keep It”, published last year, he explained his approach to the law: “It is not ‘Conservative’ with a big C focused on politics. It is conservative in the small c sense that it seeks to conserve the meaning of the Constitution as it was written. The fact is, a good originalist judge will not hesitate to preserve, protect, and defend the Constitution’s original meaning, regardless of contemporary political consequences.”

These words sound prophetic given Monday’s ruling, especially when set against Justice Alito’s dissent, where the anger of the minority is palpable: “The Court’s opinion is like a pirate ship. It sails under a textualist flag, but what it actually represents is a theory of statutory interpretation that Justice Scalia excoriated––the theory that courts should ‘update’ old statutes so that they better reflect the current values of society.”

The indignation is understandable. What was questioned here was Title VII of the 1964 Civil Rights Act, which outlawed “discrimination in the workplace on the basis of race, color, religion, sex, or national origin”. The Supreme Court had to decide if “sex” covered people who were homosexual or transgender. The originalists would think they were on solid ground. Unless you’re willing to unpick the cultural mess around the term “gender”, you would assume that “sex” is so clearly defined in the Constitution that it excludes all else.

Gorsuch, however, does the unexpected. Brilliantly and succinctly (often a feature of brilliance) he exploits the certainty of the originalist position by reframing the question so it is about sex. “An employer who fires an individual for being homosexual or transgender fires that person for traits or actions it would not have questioned in members of a different sex.” This reversal is so astute because it reseats the question on textualist bedrock, determining that “Sex plays a necessary and undisguisable role in the decision”.

By proving that “a good originalist judge will not hesitate to preserve, protect, and defend the Constitution’s original meaning, regardless of contemporary political consequences”, Gorsuch has also reminded us that nothing should be assumed. That should calm some nerves given fears that a Trump loss in November might end up at the Supreme Court. That’s when Gorsuch’s small c remaining small becomes so important.

Yet it should also remind us that the GOP becoming “the party of Trump” was always temporary. All parties exist in prolonged moments of transition but that is especially true of the Republican Party under this president. The moment is coming when we’ll be asking how long the establishment will stay loyal to him. Trumpism was a convenient binder for as long as it lasted, but the binding is beginning to fray.

Gorsuch is merely the latest to commit heresy. General Mark Milley, the Chairman of the Joint Chiefs of Staff, used the controversy of Trump’s photo opportunity outside St. John’s Episcopal Church to restate the independence of the military. “I should not have been there”, he said in an anguished apology. “My presence in that moment and in that environment created a perception of the military involved in domestic politics.”

Mitt Romney and former President George W. Bush are already refusing to support Trump in November, while Colin Powell has said that he’ll be supporting Joe Biden. Meanwhile, Tom Cotton’s controversial and (frankly) somewhat frightening op-ed in the New York Times showed that at least one contender is already shuffling for position in the post-Trump era. He is surely not going to be the last.

Republicans now fear they’ll lose the Senate. If the President continues to haemorrhage support in the polls, there will be more Republicans setting themselves for the long run-in to become the 47th president. What’s clear from today is that the 45th shouldn’t rely on Neil Gorsuch toeing a party line in order to save him.