Suppose that Ginsburg isn’t replaced this fall, Biden is elected, and he fills her seat and then replaces at least one conservative justice as well, flipping the court back to liberal control. The Democratic incentive to reform our juristocracy would diminish or evaporate, and liberalism’s self-understanding as the party of hyper-educated mandarins would come back to the fore, making progressives enthusiastic about judicial power once again.

Meanwhile, conservatives would have all of their suspicions about establishment Republicans confirmed yet one more time, and they could add the Supreme Court to the lengthening list of elite institutions in which cultural liberalism’s power seems more consolidated every day.

The likely result would be a right-wing coalition that’s angrier and Trumpier than the G.O.P. that nominated Trump himself four years ago. So our imagined Republican senator’s reward for his high-minded vote could easily be a longer-term defeat for moderate conservatism: The judiciary would be handed over to ambitious liberals, and his own party would become more populist, paranoid and hostile to any form of compromise.