In less than a year, President Donald Trump has drained many of the most important sources of American power. He is unwinding the country’s alliances, degrading its principles, walling off its economy, and subverting international institutions that serve its interests. The speed of the onslaught has made grasping all of its perils nearly impossible, especially as China and Russia pose a growing threat to the United States. But if you want to begin to see how much Trump has eroded America’s ability to win today’s great-power competition, consider the last one.

The United States won the Cold War for at least four major reasons: It built stronger partnerships than the Soviet Union did. It championed ideas about democracy and human rights that the world found more compelling than the Kremlin’s communism. It bolstered a global financial order that advanced American goals. And its open economy outperformed the Soviet Union’s closed one, allowing the U.S. to support a superior military.

This essay has been adapted from McFaul’s new book.

Today America faces a different kind of Cold War, one in which China plays a bigger role than Russia. But these same four pillars will almost certainly determine the outcome. A prudent leader would reinforce them; Trump is bulldozing them.

Perhaps no single day mattered more for America’s ultimate triumph in the Cold War than April 4, 1949. That afternoon, the U.S. joined Canada and 10 European countries in signing an agreement establishing NATO, the most powerful military alliance in the world. NATO members didn’t always agree—internal disputes erupted throughout the Cold War—but the organization played a vital role in maintaining American power as well as peace in Europe.