The contrast is striking: On May 28, Donald Trump demanded the First Amendment right of free speech for himself on privately owned social media, and then, four days later, declared war on the people, gathered on public property, as they sought, in the words of the amendment itself, “to assemble, and to petition the Government for a redress of grievances.”

The right of assembly is an important First Amendment right, one treasured by the founding generation and the First Congress, which wrote the amendment, and one re-won two centuries later at great pain by the labor, civil-rights, and anti-war movements. The show of force that swept peaceful protesters from Lafayette Square in Washington, D.C., last night was an assault—and perhaps only one of a series of assaults—on that right.

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The right of assembly had a rough go for the first century and a half of the Constitution. By the end of the 19th century, no less an authority than Oliver Wendell Holmes Jr. (the son of a founder of this magazine, and then a state judge) briskly dismissed the idea of expressive rights on public property. Public property belonged to the government, Holmes said, not to the people at all. “For the legislature absolutely or conditionally to forbid public speaking in a highway or public park is no more an infringement of the rights of a member of the public than for the owner of a private home to forbid it in his house.” The U.S. Supreme Court tersely affirmed Holmes’s opinion. “Peaceful assembly” be damned. The people were not to come “out of doors” without the permission of their rulers.

Only half a century later, in a case about the rights of labor organizers, did Justice Owen Roberts, writing for a plurality, cleanse the law of Holmes’s view of government as the owner and citizens as guests. Roberts wrote:

Wherever the title of streets and parks may rest, they have immemorially been held in trust for the use of the public and, time out of mind, have been used for purposes of assembly, communicating thoughts between citizens, and discussing public questions. Such use of the streets and public places has, from ancient times, been a part of the privileges, immunities, rights, and liberties of citizens. The privilege of a citizen of the United States to use the streets and parks for communication of views on national questions may be regulated in the interest of all . . . but it must not, in the guise of regulation, be abridged or denied.

The people own the streets—not the police, not the military, and not Donald Trump.