Anthony Kennedy announced his retirement from the Supreme Court yesterday. He’s the last of the Reagan appointees on the Supreme Court, and he’s the last of the 1980s high court justices. Kennedy turns 82 next month, and he’s earned retirement. Who comes next? And what sort of country will she or he help foster?

In January, Michael Brendan Dougherty wrote on the Kennedy-era Supreme Court, and it’s unique tendency to “swing from side to side, dispensing wins and losses to the left and the right” in any number of 5-4 cases where Kennedy has been a pivotal decider:

When normal people find out that my job involves writing or thinking about politics, they sometimes ask questions like, “Who is to blame for the government shutdown?” Or “Will Donald Trump get reelected?” Or “Will Donald Trump get us all killed?” And I try to answer these queries quickly so as not to bore them too much: The people. Probably. And, I’m not discounting it, FWIW. Among people who also do this for a living, such as my fellow writers and editors at National Review, you have in-the-weeds conversations about “tail risks” to the whole system. You ask questions like, “Will the Senate still be around in ten years?” Or, “What would cause a regime change in the United States?”

And occasionally these conversations leave you with a thought that you can’t escape, even if you feel silly bringing it up. Here’s one that’s been bothering me lately. I’ve started to think that Supreme Court Justice Anthony Kennedy may be the one man preventing the United States from political breakdown. …

The most salient feature of American political life is partisan conflict. Gerrymandering and other factors in elections have disempowered moderates in both parties and increased the power of activist groups in each political coalition. The closeness of presidential elections emphasizes that the country is divided in relatively equal camps. The American system, in the eyes of citizens, is functioning less and less like a federal system in an orderly republic. It seems more and more like a closely competitive mass democracy. So long as the presidential coalitions remain roughly competitive, partisans expect some victories in between their defeats. …

The Supreme Court’s role in this scene, with Kennedy as the swing justice, has been to moderate and restrain the ambitions of each party. Kennedy deals out victories and defeats to each side — giving slightly more defeats to social conservatives. In effect, he constrains what each side can do to the other. His mercurial jurisprudence replicates and even gives the savor of legitimacy to a closely divided country.

So I’ve started to worry that if the Court soon consolidates to the left or the right, partisans on the losing end of that bargain will swiftly lose faith in democracy itself. A non-swinging Supreme Court would give the impression of super-charging the ability of one party to act, and restraining its competitor. A consolidated Supreme Court could open up whole new fields of legislation for one side to act against the other. At that point, what would happen?

… I can foresee both parties’ reaching for extraordinary measures if they felt that the Supreme Court had become the cat’s-paw of one party. The obvious bag of tricks includes states’ trying to nullify laws. Or one party could try to pack the Supreme Court with new justices to rectify or reverse the consolidation.

In other words, I’ve begun to think that what’s left of our constitutional regime relies on the impression of legitimacy given to it by a swinging Supreme Court, the Kennedy Court. Maybe we’ll get lucky and the relative strength of our respective presidential coalitions and the respective health of the Supreme Court justices will align to keep the court balanced roughly the way it is, preserving what’s left of our constitutional order. But lately, I’ve begun to doubt it.

If the accidents of history have made Anthony Kennedy our philosopher king, his death means American regime change.

One of the reasons that Dougherty calls Anthony Kennedy our “philosopher king” is due to his 1992 Planned Parenthood v. Casey assertion that, in a single sentence, probably provides the key to understanding his approach to jurisprudence: “At the heart of liberty is the right to define one’s own concept of existence, of meaning, of the universe, and of the mystery of human life.” It’s this capacious and basically libertarian attitude that has supported his philosophical (if not jurisprudential) approach to sex, abortion, marriage, speech, and more. We’ll probably never have someone like Kennedy back on the court.

I think Dougherty’s analysis is overly dramatic, but it’s true that Kennedy (along with Ruth Bader Ginsburg) developed distinctive cult-like followings among certain politico-types. With Kennedy’s retirement, and Ginsburg’s eventual departure, the court’s character will change.