What underlies malaise of the West’s leading nations?

Is it coincidence or contagion, this malady that seems to have suddenly induced paralysis in the leading nations of the West?

With lawyer-fixer Michael Cohen’s confession that he colluded with Donald Trump in making hush money payoffs to Stormy Daniels and Karen McDougal, America’s stage is set for a play that will run two years.

As Democrats test the waters for a presidential run by savaging Trump, the establishment Trump detests and defeated in 2016 will use every weapon in its considerable arsenal to break and bring him down. The outside world will see America again as a house divided.

Consider, then, the situation of our old ally Great Britain.

Prime Minister Theresa May was just forced to pledge she would not lead her party in the next election — to survive a no-confidence vote in Parliament. The vote was called after May had to cancel a vote on the Brexit plan she had negotiated with the EU, when it was evident a coalition of Tories and Labor would vote to kill her plan.

May has been humiliated. Yet the clock is running toward a March deadline for concluding a Brexit deal. And no plan acceptable to both Parliament and the EU is on the table. The possibility exists that Britain could simply crash out of the EU, causing severe economic damage to both.

In France, after four Saturdays of anarchy, arson, looting and vandalism of her national monuments, President Emmanuel Macron capitulated to the rioters. He withdrew the fuel tax that triggered the uprisings. One poll puts Macron’s approval at 21 percent. The idea that he can replace Angela Merkel as the recognized leader of the EU seems ridiculous.

As for Merkel, hailed as leader of the West in the time of Trump, her party and coalition lost so much support in the recent election that she stepped down as leader of the CDU and pledged not to run for another term as chancellor.

Europe’s fourth-largest economy, Italy, is now led by a coalition of the populist-left Five Star Movement and populist-right Lega party. The coalition seeks greater freedom on spending than Brussels is willing to allow, and a halt to migration from across the Med. The EU has never seemed less united. What are the underlying causes of these 21st-century crises of Western democracies?

Certainly, globalization, with its creation of ties among transnational elites at the expense of nationstates and their indigenous peoples is one. Capitals — Washington, London, Paris, Berlin — seem ever more distant from the countries they rule.

Then there is demography. The native-born of almost all Western nations are aging, shrinking and dying. Death rates exceed birth rates. Though peoples of the West are living longer, they are producing fewer children to replace them.

At the same time, Western elites have welcomed foreign workers and left borders unsecured against mass migration. And the people coming in are not assimilating as children of 19th- and 20th-century European immigrants to the USA had largely done by 1960.

A consequence and related cause is the rise of tribalism, or ethno-nationalism, the search for identity and community with one’s own. Loyalties to family, tribe, neighborhood, culture and country appear paramount, rising above intellectual and political alignments.

The heart has reasons of which reason knows nothing, said Pascal. And so it does.