Donald Trump has given the world a chilling preview of his foreign policy.

In his inaugural address as president, the businessman promised to break with decades of international trade policy and “put America first”.

Trump said he would protect the United States “from the ravages of other countries making our products, stealing our companies and destroying our jobs.”

“Protection,” he maintained, “will lead to great prosperity and strength.”

That is not what the last century has taught us.

Misguided quest for autarky

After two world wars, Americans recognized that the misguided quest for autarky could only lead to conflict among nations. They deliberately built an international system under their protection to liberalize the movement of capital, goods and people around the globe — to great effect. Europe and East Asia have enjoyed six decades of peace and prosperity as a result, which, in turn, has made America richer as well.

Now Trump proposes to tear it all down.

The contrast with his Democratic predecessor could scarcely be greater.

Four years ago, in his second inaugural address, Barack Obama called for a “world without walls.”

In a series of interviews in the last few months, the outgoing president repeatedly counseled Americans against disengagement, arguing that the international order has brought them tremendous security and wealth.

Betrayal of the elites

Trump disagrees.

On Friday, surrounded by congressmen, senators and former presidents, the man who refuses to divest himself from his business interests alleged that elites have for decades colluded with foreign industry to enrich themselves at the expense of the American worker.

He claimed they had subsidized the armies of other countries while undercutting the American soldier; defended the borders of other nations while refusing to secure their own.

All this is demonstrably false. But Trump’s rhetoric contains just enough truth to be credible to his supporters.

Low-skilled workers — not just in the United States, but across the Western world — have lost out as globalization benefits those with college degrees.

European countries and Japan have underinvested in their armed forces, free riding on American might.

But that is by design and has done nothing to undermine America’s military superiority.

To the contrary: America is faraway the strongest military power on the planet.

When Trump talks about a “depleted” armed service, he can’t in all seriousness refer to the one he now commands.

Contradictions

Trump, the first Republican leader since 2003 to repudiate invasion of Iraq, also announced the end of democracy promotion. Under his presidency, he said, America would no longer seek to impose its way of life on others.

Yet he also called for a united front against Islamic terrorism, which, he said, “we will eradicate completely from the face of the Earth.”

The contradictions here are numerous — and do not seem to perturb Trump in the slightest.