IT’S NOT easy to run afoul of two constitutional amendments in 140 characters. Whether he realizes it or, more likely, not, President-elect Donald Trump did so in this Twitter outburst Tuesday: “Nobody should be allowed to burn the American flag — if they do, there must be consequences — perhaps loss of citizenship or year in jail!” The Supreme Court ruled in 1989 that the First Amendment protects burning the flag in protest. The high court ruled in 1967 that the 14th Amendment not only grants U.S. citizenship to “all persons born or naturalized” in this country; it also forbids the government from taking citizenship away from them.

In effect, then, Mr. Trump is proposing two constitutional changes — both of which provide further evidence of his tendency to address differences and disagreements within American society by suggesting new limits on their expression, or by excluding people from the American community altogether. We have seen this tendency at work in his call to “open up” libel laws — i.e., make it easier for public figures such as himself to sue when newspapers criticize them — and in his floating a religious test for entrants from abroad.

[No, you couldn’t strip flag-burners of citizenship, even if flag-burning could be made a crime]

On flag-burning, his view is no doubt popular: Forty-eight states and Congress outlawed it before the Supreme Court ruled in 1989; subsequent Congresses voted repeatedly to reinstate such a rule in various ways, albeit not by the two-thirds of both houses necessary to send a constitutional amendment to the states. Nor does the political right have a monopoly on burn-banning. Justice John Paul Stevens, one of recent history’s most eloquent judicial progressives, dissented, passionately, in the flag-burning case. In 2005, none other than Sen. Hillary Clinton (D-N.Y.) co-sponsored (unsuccessfully) a bill to bar flag-burning when intended to “incite violence.”

Certainly the flag is the greatest of our national symbols, an emblem of liberty, unity and democracy borne aloft not only by American soldiers in battle, but also by the prisoners of Dachau concentration camp who secretly sewed one, then waved it to welcome U.S. Army troops when they arrived in 1945 — and by the marchers at Selma, Ala., who demanded their own portion of liberation 20 years after that. Its desecration rankles, deeply.

Here's what you should know about President-elect Donald Trump's Nov. 29 tweet calling for a ban on burning the U.S. flag. (Sarah Parnass/The Washington Post)

But burning-banners’ arguments ultimately founder on the rock of the First Amendment, which, if it means anything, means that the people have the right to express their views through the widest possible range of nonviolent means, even — or, perhaps, especially — those views that offend most deeply. It is ironic that a man elected on a platform of opposition to hypersensitive “political correctness” would embrace a flag-burning ban. Another irony: Among those who understood the democratic necessity of protecting even the most unpopular expression was Justice Antonin Scalia, whom Mr. Trump purports to admire, and whose successor he will soon nominate. Many fellow conservatives disliked it, but Scalia often cited his vote to protect flag-burning as an example of how the Constitution limited his power, and that of all other government officials, to stamp out ideas they personally despised.

It would be President Trump’s prerogative to urge Congress, and the states, to rewrite the First Amendment along more repressive lines. Like Scalia, we prefer the original.