Partisans on the left and right are reacting to Monday’s Supreme Court decision on presidential immunity based on how it affects the fate of Donald Trump. That’s a blinkered view that ignores the long-run implications for the American republic. The 6-3 Court majority rightly focuses on the institution of the Presidency, and the ability of all Presidents—not merely the last one—to act in the national interest free from prosecution for official acts. *** The opinion by Chief Justice John Roberts in Trump v. U.S. is a landmark on executive power. It was also predictable based on the Court’s 1982 opinion in Nixon v. Fitzgerald, which said a President has absolute immunity from civil suits for acts within the “outer perimeter” of his duties. The Court ruled on Monday that the threat of criminal prosecution for official acts would be even more debilitating to executive power.

“A President inclined to take one course of action based on the public interest may instead opt for another, apprehensive that criminal penalties may befall him upon his departure from office,” writes the Chief for the six conservative Justices. “And if a former President’s official acts are routinely subjected to scrutiny in criminal prosecutions, ‘the independence of the Executive Branch’ may be significantly undermined.”

The Chief goes on to provide a nuanced ruling that is far from a total victory for Mr. Trump. The Court properly reads the Constitution to offer absolute immunity for actions within the core plenary powers of the executive. This means that a President can’t be prosecuted for actions related to national security, intelligence, or foreign policy. He can’t be prosecuted, for example, for deaths that occur from ordering a drone strike. And he can’t be prosecuted for his communications with the Attorney General on his investigative decisions. This disqualifies part of special counsel Jack Smith’s narrative against Mr. Trump in the Jan. 6 indictment. But the Court rejected Mr. Trump’s claim that all presidential acts have absolute immunity.

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