America has always been an experiment in the limits of diversity.

How deeply and in how many ways can a people differ and disagree, and even disapprove of one another's ways of life, and still remain "a people" — a community with enough shared values to stay united and, as necessary, defend itself?

Born in revolution, lacerated by Civil War caused by racial injustice and strife that divide us still, unsettled by repeated waves of immigration aggravating ethnic, religious and class tensions — the nation has weathered many splintering storms yet held shakily together, so far.

So maybe today's worrisome divides will also prove bridgeable, even though some of them seem to test new boundaries.

Most coherent human cultures have enjoyed a tolerably firm agreement about basic social norms like what a marriage looks like. (Or certainly about bathroom rules — who should answer nature's call where.) There may be no one "right" answer to such questions — but most societies have settled on one answer for themselves.

Can America find a way to accommodate an ever-widening array of differences, even on such matters as these? Or will those who differ with new customs and definitions simply be forced to disown their own beliefs and affirm a new orthodoxy?

One American tradition that hasn't changed is that such conflicts about what freedom and tolerance really mean, and for whom, tend to end up in American courts. A notable ruling on accommodating clashing diversities was handed down in August. Both the case and the judge who authored the decision hail from Minnesota.

The three-year-old dispute involves Carl and Angel Larsen, devout Christians who operate a videography business in St. Cloud. The Larsens want to expand into making wedding videos but feel compelled by their faith to decline to craft films celebrating same-sex marriages. They sued the state of Minnesota in federal court, arguing that state anti-discrimination law would require them to artistically endorse same-sex as well as opposite-sex weddings, and in the process would violate their freedoms of speech and of religion.

A federal district judge in Minneapolis rejected the Larsen's claim in 2017. But a panel of the Eighth U.S. Circuit Court of Appeals overturned that ruling Aug. 23 and held, in a 2-1 decision, that the Larsens have a constitutional right to determine what beliefs they will and won't express through their filmmaking.

It's been clear ever since same-sex marriage began its remarkable march toward nationwide legalization that the marketplace for wedding services was likely to produce conflicts of conscience.

Would florists or hairstylists or disc jockeys who sell services to wedding parties, but have religious objections to same-sex unions, be compelled to participate in events that contradict their beliefs?

The answers from courts remain mixed and indecisive, but the Larsens' victory is notable.

Not the least-interesting twist in the case is that the jurist who authored the ruling in the Larsens' favor is Judge David Stras, who was on Minnesota's state Supreme Court when President Donald Trump appointed him to the federal appeals bench in 2017.

While vocally supported by several liberal former colleagues on the state court, Stras was labeled too conservative and his confirmation was held up by former U.S. Sen. Al Franken, D-Minn., in a standoff that inspired Senate Republicans to discard a Senate tradition that had long allowed home-state senators to prevent judicial appointments. Trump has filled many federal court vacancies since then.

One moral to this tale all can agree on is its reminder that judicial appointment powers matter.

As for the collision of rights in the Larsens' case and others like it, much seems to depend, at least in federal cases, on the distinction between government rules regulating mere "conduct" or regulating "speech." That turns on whether a particular wedding product or service can be seen as a form of personal expression by the provider.

Those who simply rent out a wedding venue or cater a reception would seem to have little basis to escape the typical command in an anti-discrimination law that "public accommodations" must serve all comers, regardless of race, religion, sexual orientation, etc. The lower court and the dissenting appeals court judge saw the videographers the same way.

But photographers, musicians and other creative artists who offer their efforts for hire may have more latitude, at least in front of judges like Stras. His reasoning will ironically discomfort many progressives precisely by broadening the range of diversities and freedoms that must be tolerated in the process — tolerating even "discrimination" at least where both "speech" and religious faith are involved.

"Even anti-discrimination laws," Stras wrote in the Larsens' case, "as critically important as they are, must yield to the Constitution." And under the Constitution, he added, "speech is treated differently."

Requiring the Larsens to extol same-sex marriage, Stras suggested, would be like requiring an ardent atheist singer to "perform at an evangelical church service."

The U.S. Supreme Court (the Larsens' next stop should the state appeal) wrestled with similar issues last year in the Masterpiece Cakeshop case. The court ruled 7-2 that the bakery's rights had been violated when Colorado officials cited it for discrimination in declining to make a cake for a same-sex wedding.

But the high court ruled in that case on the basis of anti-religious bias displayed by Colorado decisionmakers. It debated, but did not resolve, whether baking and decorating a cake — however artistic a "masterpiece" — could be seen as constitutionally protected "speech."

In another noteworthy detail, the ambiguous ruling in the cake controversy was written by now-retired Justice Anthony Kennedy, a champion of both free speech and gay rights, and the author of the 2015 ruling that legalized same-sex marriage nationwide.

Kennedy was replaced last fall by Trump appointee Brett Kavanaugh, who seems unlikely to be a stronger defender of same-sex marriage or any less sympathetic to religion and speech rights.

And so America continues (let's hope) — one nation, endlessly divisible.

D.J. Tice is at Doug.Tice@startribune.com.