If you don’t like the way your political party leans, just wait a while.

That paraphrase of the old saw about the weather in Maine (or just about anywhere that isn’t San Diego) exaggerates the situation, but look at how the two major political parties have switched places over the past few decades on the issue of free speech.

Anyone who remembers the “Free Speech Movement” might think of its leaders as liberals and Democrats. For the most part, they were. Students at the University of California in Berkeley wanted the school to allow political activity and to support free speech and academic freedom in general. No civil libertarian would disagree.

After four months of protest in 1964-65, Berkeley set up rules to permit new freedoms on campus to organize politically and to speak openly. The activism spread to hundreds of other campuses and fueled drives for civil rights and against the Vietnam war.

Even as liberals/Democrats widely favored the free speech and assembly, Republicans were reticent. In the mother-ground of the movement, Ronald Reagan used the university as a foil to win election in 1966 as governor of California. Conservatives were heartened, and the movement fathered by Barry Goldwater had found a mother in Reagan.

In a little more than half a century, the ball has gone 180 degrees. Today, it is liberals who clamp down on open speech. Consider these:

• A poem this month in The Nation, a prominent leftist publication, stirred an outcry and drew what amounted to a retraction from the magazine’s poetry editors and from the poet. The offense? The white poet seemed to be using black “ghetto” language.

• Readers of The New York Times objected when the paper added Sarah Jeong to its editorial board. Jeong, a Korean-American technology writer, has a history of provocative Twitter tweets, often personal and offensive.

• Facebook, Spotify, Apple and YouTube, among others, last week virtually banned posts by Infowars, a website run by Alex Jones, a right-wing conspiracy theorist. The companies cited their policies against hate speech, rather than the posting of fake news by Infowars. You can bet that his banning will be widely condemned this afternoon at the Unite the Right demonstration in Washington, D.C.

Let’s make a distinction. As a public university, Berkeley was subject to federal laws and the Constitution. But private institutions — colleges, publications, clubs — are not bound by the Constitution. A private college is free to, say, ban the Koran, though that would suggest the college isn’t serious about free inquiry or the pursuit of truth. A private group, such as Apple, is free to permit or ban any person or idea from its turf.

That said, the growing tendency of liberal/left/Democratic folks to stop inquiry troubles. Why are those who protest the language in a poem, the tweets of a writer and the anti-social-media posts of a nutcase like Jones so willing to ban those people and those ideas?

Are they afraid to let us think for ourselves?

Without the foofaraw, I wouldn’t have read the poem by Anders Carlson-Wee. I won’t condemn his use of black “ghetto” English, but I will condemn his lousy grammar and lousy syntax. Give him a copy editor, and he might have a decipherable poem. Maybe he meant to say one shouldn’t present oneself as others see one but as one sees oneself. Or, maybe he meant something else. Hard to wade through the mud to the other side.

Still, if condemnations are to be handed out, they should go to the poet, the poetry editors and The Nation for trying to keep me from trying to figure out what he wrote.

When The Times took Sarah Jeong on board, many of its presumably sophisticated readers objected because she had blasted out such tweets as “White men are bull—,” “Cancel white people” and “Oh man it’s kind of sick how much joy I get out of being cruel to old white men.”

This old white man, who never had heard of Jeong, is offended. But he agrees 100 percent with Times columnist Bret Stephens, who on Thursday wrote, “We should call many of these tweets for what they are: racist. But the criteri(on) for racism is either objective or it’s meaningless. If liberals get to decide for themselves who is or isn’t a racist . . . conservatives will be within their rights to ignore them.”

Interestingly enough, when The Times hired Stephens away from the editorial pages of The Wall Street Journal, which some might call Fox “News” for intellectuals, Times readers uproared similarly, and hundreds canceled their subscriptions.

I read Stephens regularly and especially enjoy his dialogues with The Times’s Gail Collins. It is a right-left debate that entertains and informs. That’s a worthy goal for any editorial page.

The anti-social-media giants banning of Alex Jones is dicier. Jones may be certifiably cuckoo. Among other “ideas” he has put forward is that the murder of 20 children and six teachers at Sandy Hook was a hoax and that 9/11 was carried out by the government.

Clearly, he’s at least a full bubble out of plumb. But what happens when the anti-social-media guys start banning less controversial “ideas.” What happens if they decide posts don’t need to be off the wall in order to be off the internet?

As someone who occasionally publishes an opinion in the Sun Journal, I wonder how far the private limitation of ideas can go. Let the readers decide.

Bob Neal prayed at a church in Newtown, Connecticut, a month after Sandy Hook. The 26 memorial wreaths there indicated the townspeople believed it really happened.