What would you think if you were walking past Boston City Hall one day and saw at the building’s entrance an 83-foot-tall flagpole waving a banner with an enormous red Christian cross on it?

Well, if you were a churchgoing Christian you might think that was OK. Maybe.

But if you were a member of a different religion or if you were a nonbeliever — or if you cared about the separation of church and state — you would almost certainly wonder what on earth was going on and why your government was waving the symbol of Jesus Christ in the faces of those citizens who are not Christians.

In the United States, after all, government may not endorse or promote one religion over another, or over no religion at all. The Constitution makes that clear in the 1st Amendment, which says that the government “shall make no law respecting the establishment of religion.”

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I know as a non-Christian American that I’m pleased and proud to live in a country that so adamantly protects the rights of the nonmajority and doesn’t impose one set of beliefs on the whole country.

That’s why the U.S. Supreme Court ought to rule against Harold Shurtleff and the religious organization he runs, Camp Constitution, who say their constitutional rights were denied when they were refused permission in 2017 to hang a cross-bearing Christian flag on a flagpole outside Boston City Hall.

Oral arguments in Shurtleff vs. Boston are scheduled for Jan. 18.

But I don’t want to oversimplify. There are nuances to the case.

Shurtleff had hoped to participate in a city of Boston program that allows third-party organizations to apply to hang their flags from one of the three flagpoles at City Hall.

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Mostly, that privilege has been extended to flags of other nations. But it has also been granted in recent years to an organization flying the LGBT pride flag as well as to groups celebrating transgender rights, Malcolm X day, Mother’s Day and others. The third-party flags are raised where the flag of the city usually flies, next to poles carrying the banners of the United States and the Commonwealth of Massachusetts.

No group had ever been turned away when it had applied, so Shurtleff figured that he’d get the go-ahead too.

But the city refused him, saying it would be a violation of the 1st Amendment’s establishment clause to hang the Christian flag from a government flagpole.

Shurtleff and his group didn’t buy it. They sued, arguing that by “taking all comers” in the past, the city had transformed the flagpole into a “public forum,” and that the message being sent by the flag was now “public speech” rather than “government speech,” a critical distinction in the law.

That means, they argued, that government could no longer decide which messages were acceptable and which were not. Religious messages would be OK. In fact, it would be a violation of the 1st Amendment for the city to deny their application on the basis of their viewpoint or the content of their message.

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They said the flagpole had, in effect, become a public soapbox on which all points of view could be expressed.

The American Civil Liberties Union and the Biden administration agree with that position; lower courts disagree.

But I’m skeptical that a towering flagpole in the center of government, in front of City Hall, can really be a “public forum.” Most reasonable people would obviously see a flag flying there as an expression of government speech.

It’s not like a demonstration in the plaza outside City Hall, where it’s clear that the banners and signs represent the speech of the protesters. A flagpole outside a government building is official. It’s institutional. What hangs there surely appears to have been approved and condoned by government. And for that reason, it shouldn’t carry an endorsement of Christianity or any other religion.

Boston argued, additionally, that it didn’t actually “invite all comers” to fly flags, that the flagpole wasn’t a public forum because the city kept a measure of control, requiring that outside groups apply and allowing only flags that sent messages that met with government approval.

The Supreme Court will have to sift through the nuances. I hope the justices will decide that the Christian flag shouldn’t wave in front of City Hall.

But I also believe Boston should never have instituted its flag program in the first place. It should have been obvious that letting outsiders fly flags from government flagpoles would blur the line between private speech and government speech.

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It’s almost inevitable that when government lends out its own traditional speaking spaces, someone will come along to promote a message the government doesn’t want to promote.

For instance, when Texas offered specialty license plates with graphics, it was predictable that someone would want a Confederate flag on theirs. That case went to the U.S. Supreme Court, where Texas won.

In Georgia, the International Keystone Knights of the Ku Klux Klan sought, under a state “adopt-a-highway” program, to have the group’s name posted on signs along a one-mile stretch of State Route 515. The Klan won in state Supreme Court.

Duh! How could local governments not see these disputes coming?

But even if Boston wasn’t entirely in the right, it is Shurtleff’s argument that is the more troubling. If it prevails, we could soon have not just religious flags waving on the flagpole at City Hall, but Nazi swastikas and Klan banners as well.

The Constitution protects speech by religious organizations, white supremacist groups, advocates for the homeless, anti-tax protesters and everyone else. By all means, let them wave signs and banners galore. But not on city flagpoles.

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Nicholas Goldberg is an associate editor and Op-Ed columnist for the Los Angeles Times. He previously served 11 years as editor of the editorial page and was also a former editor of the Op-Ed page and the Sunday Opinion section. While at New York Newsday in the 1980s and 1990s, Goldberg was a Middle East correspondent and political reporter. His writing has been published in the New Republic, New York Times, Vanity Fair, the Nation, Sunday Times of London and Washington Monthly, among other places. He is a graduate of Harvard University.

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