So much for the claim that Donald Trump’s strident campaign rhetoric about Muslims rendered him unfit to wield the powers of the presidency. The Supreme Court will have none of it.

That’s the bottom line in the justices’ blockbuster decision to back President Trump against a suit by Hawaii on the so-called Muslim travel ban, overruling the lower courts.

Not only that, but the decision was a major blow to the “judicial resistance” — the attempts by judges to constrain Mr. Trump’s clearly vested powers because they don’t like the president who’s wielding them.

The vote may have been a narrow five to four. It was backed up, though, by a thumping decision by Chief Justice Roberts, eviscerating claims by the judicial resistance to Mr. Trump.

All sorts of issues were swept away by the majority of justices: Anthony Kennedy, Samuel Alito, Clarence Thomas and Neil Gorsuch joined Chief Justice Roberts.

At the heart of the case, though, lay what the justices called “a series of statements by the president” that cast doubt on the “official objective” of his extreme vetting.

The justices cited Mr. Trump’s call during the campaign for a “total and complete shutdown of Muslims entering the United States until our country’s representatives can figure out what is going on.”

They also referenced an interview by Mayor Giuliani after Mr. Trump was sworn in. Mr. Giuliani asserted that Mr. Trump had referred to a “Muslim ban” and asked to be shown “the right way to do it legally.”

Tweets by the President made well after Hawaii began its litigation were also cited by the justices. They noted the President “retweeted links to three anti-Muslim propaganda videos.”

They also dealt with attempts by Mr. Trump’s opponents to drag into the litigation the case of Fred Korematsu. He was the American-born son of Japanese parents who’d fought internment in World War II.

Korematsu, decided in 1944, is an infamous case. The Supreme Court okayed FDR’s roundup of persons of Japanese descent and their placement into internment camps.

The justices plainly thought about this. That was made clear by Justice Sotomayor, in an eloquent dissent arguing that there were “stark parallels” between the Trump case and Korematsu.

Just as FDR did in Korematsu, Sotomayor wrote, Mr. Trump “invoked an ill-defined national-security threat to justify an exclusionary policy of sweeping proportion.”

The majority, however, swept Korematsu aside. “Whatever rhetorical advantage the dissent may see in doing so,” the majority wrote, “Korematsu has nothing to do with this case.”

It called the internment of American citizens “solely and explicitly on the basis of race,” as happened in Korematsu, “objectively unlawful and outside the scope of presidential authority.”

In an extraordinary aside, the majority went so far as to label Korematsu “gravely wrong the day it was decided.” It said it “has been overruled in the court of history.”

The majority insisted, though, that it’s “wholly inapt” to liken the “morally repugnant” policy in Korematsu to “a facially neutral policy denying certain foreign nationals the privilege of admission.”

What Mr. Trump had done, it ruled, is “well within executive authority and could have been taken by any other president.” It was done under a law Congress passed and could adjust at any time.

So clearly did the high court assert Mr. Trump’s authority under the Immigration and Nationality Act that this case could well be remembered for its weakening of the judicial resistance seeking to use the courts to undo the voters’ choice in 2016.

It’s not just lower-court judges ignoring the president’s statutory authority. Or requiring, the court noted, Mr. Trump to jump through hoops that no court ever imposed on his predecessors.

There’s also the question of federal-district judges handing out “universal” injunctions that reach way beyond the parties involved — affecting the whole country or even the world.

The district judge in Hawaii — Derrick Watson — had enjoined Mr. Trump from implementing the travel restrictions anywhere. Chief Justice Roberts felt no need, in this case, to sort out the issue.

Clarence Thomas, in a concurrence, went further. He called such orders “legally and historically dubious,” warning that if the lower courts continue using them, the Supremes would be “duty-bound” to adjudicate.

So the judicial resistance is on notice.

This column first appeared in the New York Post.