What is America’s cause in today’s fast-shifting world?

After being sworn in for a fourth term, Vladimir Putin departed the Kremlin for Annunciation Cathedral to receive the televised blessing of Patriarch Kirill of the Russian Orthodox Church.

The patriarch and his priests in sacred vestments surrounded Putin, who, standing alone, made the sign of the cross.

Meanwhile, sacred vestments from the Sistine Chapel were being transported by the Vatican to New York’s Metropolitan Museum of Art to adorn half-clad models in a sexy show billed as “Heavenly Bodies: Fashion and the Catholic Imagination.”

In Minsk, Belarus, on May 17, to celebrate International Day Against Homophobia, Transphobia and Biphobia, Britain’s embassy raised the rainbow flag. Belarus’s Ministry of Internal Affairs was not amused:

“Same-sex relationships are a fake. And the essence of fake is always the same — the devaluation of truth.”

What is going on? A scholarly study sums it up: “The statistical trends in religion show two separate Europes: the West is undergoing a process of secularization while the post-socialist East, de-secularization.”

One Europe is turning back to God; the other is turning its back on God.

And, so, what do we Americans stand for now?

In World War II, Americans had no doubt they were in the right against Nazism and a militaristic Japan that had attacked us at Pearl Harbor.

With the moral clarity of the Cold War gone, how do we rally Americans to fight on the other side of the world in places most of them can’t find on a map?

A weekend article in The Washington Post discusses the strategic difficulty of our even prevailing, should we become involved in wars with both Iran and North Korea.

“You would expect the U.S. and its allies to prevail but at a human and material cost that would be almost incalculable, particularly in the case of the Korean example,” said Rand researcher David Ochmanek.

One wonders: How many of these potential wars — with North Korea, Iran, Russia, China — could we fight without having America bled and bankrupted.

Only one great power survived the last century as a world power. The German, Russian, Austro-Hungarian and Ottoman empires did not survive World War I. World War II brought to an end the British, French, Italian and Japanese empires.

The Soviet Union and the United States were the only great surviving powers of World War II, and the USSR itself collapsed between 1989 and 1991.

Then, in 1991, we Americans started down the road of empire, smashing Iraq to rescue Kuwait. Heady with that martial triumph, we plunged into Afghanistan, Iraq, Libya, Syria and Yemen.

Though still embroiled, we are now talking war with North Korea or Iran, or even Russia or China, the former over its annexation of Crimea, the latter over its annexation of the South China Sea.

What is America’s cause today?

Defeating Nazism and fascism was a cause. Defending the West against Communism was a cause. But what cause now unites Americans?

Perhaps our mission is to defend and protect what is vital to us, to stay out of foreign wars where our critical interests are not imperiled, and to reunite our divided and disputatious republic — if we are not too far beyond that.