On top of Mount Royal, the hill that gave Montreal its name, is a cross. A great big cross, actually, 31.4 metres high and lit up at night, seen for miles around.

Most Montrealers don't give the cross much thought. It's there, it's been there forever; the symbol of a mostly Catholic city in a mostly Catholic province.

Then: the Mojave cross on Sunset Rock, the subject of a U.S. Supreme Court case, in an undated photo from at least 10 years ago. (Courtesy Liberty Legal Institute, Henry and Wanda Sandoz/Associated Press)

That Montreal's cross remains standing — as government property on government property — is one of the big differences between Canada and the United States.

Down here, most likely, it would have to be covered up or removed; at the very least, it would be the subject of some sort of court order.

That is because the U.S. Constitution says the following: "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof."

Meaning if you want to put up a cross, or pray before a six-pointed star, or prostrate yourself beneath a crescent moon, go right ahead. Just keep the government out of it.

Here, government is strictly forbidden from promoting one God over another, or any God at all, for that matter.

Another cross

It's an excellent rule, one that recognizes the natural inclination of religions to tell people how to live their lives.

It also ensures those religions remain divorced from society's enforcement powers, the way they aren't in, say, Saudi Arabia.

Because of that constitutional rule, Jewish children here do not have to repeat Christian prayers in schools. (Honestly, no Jew should ever be obliged to sing Onward Christian Soldiers, as some of my Jewish classmates had to do 40 years ago when I was a student in Quebec.) It's a rule that has stymied the efforts of Bible-belt school boards to teach "creationism" — ie. religion — in schools.

It's a rule that restrains the millions of enthusiastically evangelical Americans who believe this is a Christian nation, love it or leave it.

And it's a rule that ultimately ensures peaceful resolution of religiously tinged disputes.

Here, such matters are settled in court, rather than by guns and bloodletting, as is the case in so many other countries.

Now: the Mojave cross in this 2009 photo, sheathed in plywood to maintain the separation of church and state. (Associated Press)

That is what is happening right now, in Washington, where the U.S. Supreme Court is deciding the fate of a cross that's been sitting on a hilltop in California's Mojave National Preserve, which is government land, for the past 75 years.

Sheathed in plywood

The cross was erected as a monument to war dead.

But since 2002, when a former federal employee filed a federal lawsuit claiming his First Amendment rights were being violated, the cross has been covered.

It now sits atop Sunset Rock like an inexplicably blank billboard, sheathed in plywood.

Many devout Christians consider this sort of thing — courts interfering to keep religion off government property — to be religious persecution.

At their urging, Congress ordered the National Park Service not to remove the cross, designated it a national memorial, and has tried to transfer Sunset Rock to private hands, so as to circumvent the constitutional ban.

The courts in California have been unimpressed with that end run and so the matter arrived in Washington last week.

In the hearing before the high court, the issue seemed to turn on the strange argument that a cross is not necessarily a religious symbol.

Veterans' groups made that case and at least one Supreme Court justice, Antonin Scalia, seemed to agree.

The right to offend

In any event, the court will eventually rule and that will be that. Either the plywood sheath will come off, or the cross will come down.

It is a testament to the rule of law, and the consent of Americans to be governed by it, that the cross's plywood sheath remains undisturbed in this most religious of countries.

Imagine, alternatively, what would happen if authorities in certain Muslim countries decided to cover up a crescent moon, or if the Israeli courts ordered a Star of David concealed.

Or, for that matter, if Montrealers awoke one morning to find the big cross on Mount Royal hidden from view.

Now, the First Amendment provides another constitutional right here and that one is before the high court now, as well.

It is the right to offend, and it is nearly absolute.

No criminal penalty or punishment can be imposed for hateful speech and very little expression is roped off by law, no matter how repugnant.

The American view is that if you don't like what's being said, argue with it or just don't listen. And if you don't like what you're being shown, don't watch it.

Not a love story

That devotion to free speech is another thing that separates the U.S. from Canada, as well as from many other Western countries, most of which do censor speech and expression.

Canada, for example, has "hate speech" laws and it wasn't so many years ago that the Ontario censor forbade public showings of the National Film Board anti-pornography documentary Not a Love Story, on the grounds that the documentary itself showed naughty bits the provincial government felt the public shouldn't see.

That ruling wouldn't have lasted long down here. In this country, the dead, censorious hand of state is restrained by the bedrock of constitutional law.

There are some exceptions, admittedly. One is for child pornography. Another is for the direct incitement to specific violence.

Still another, at least for the time being, is anything displaying cruelty to animals.

Crush videos

The law prohibiting the display of animal-torture videos was passed 10 years ago to deal with so-called "crush videos."

These apparently served a niche market of consumers who achieve, um, sexual gratification from seeing women in high heels crush small animals with their shoes. But give prosecutors a law and they'll use it. In 2004, the justice department prosecuted Robert Stevens, a Virginia man who sold dog-fighting videos.

Dog fighting itself is illegal and you can go to prison for staging it, as former NFL quarterback, Michael Vick, found out.

But Stevens, who did not stage dogfights, was sentenced to 37 months — a longer term than the 23 months handed Vick — for selling videos.

That case arrived at the high court last week, too. And the federal lawyers sent to defend the law had a hard time of it.

The judges had some uncomfortable questions. Such as, what about videos of bullfights?

Those, replied the government lawyers, would be protected under exemptions for educational and artistic material.

What about videos of sheep hunting, deer hunting, fox hunting, or the forcible stuffing of geese to produce foie gras? Educational? Artistic?

Another judge asked whether Congress would have the right to regulate a "human sacrifice channel."

And Justice Scalia, a hunter himself, declared that it is not government's role to decide what are people's worst instincts.

From the perspective of a foreigner, the hearings had a silly ring.

The nine most senior jurists in the land spending two days pondering whether to uncover a cross in the desert and whether dog-fighting videos are constitutionally protected expression.

These are peculiarly American arguments. No one else has them. But they are worth having.