I have always been a cockeyed optimist about America. That’s because, in part, of my own family story: We came here in 1976 as penniless refugees from the Soviet Union and found a land of freedom and opportunity. It’s also because of my reading of history, which led me to conclude that, for all of its undoubted problems, the United States has been the greatest force for good in the world over the past century. And it’s due, finally, to my life experience: Having lived long enough to see predictions that America would be overtaken by the Soviet Union, Japan or the European Union proved wrong, I became skeptical of declinism.

But my faith in America has been badly shaken by more than two years of Trumpism. I now fear that the United States’ days as a superpower may be numbered, especially if President Trump wins a second term — as well he might.

I do not doubt that the United States will continue to be free, wealthy and militarily strong. Although Trump is trying his damnedest to undermine our democracy, our institutions are strong enough to survive his onslaught. Despite his trade wars and fiscal irresponsibility, our economy remains a world-beater. Our gross domestic product is still 1.5 times larger in nominal terms than China’s, and our per-capita GDP is more than three times larger. And, though our relative military advantage is waning, our armed forces remain the most powerful in the world.

But it’s one thing to have great power; it’s another thing to be a great power. After World War II, the United States became an “empire by invitation” whose power projection depended on popular support at home and abroad. Both are now in peril.

Americans’ backing for international leadership began to wane after the end of the Cold War and suffered a body blow after the Iraq War. President Barack Obama promulgated a “leading from behind” foreign policy and declared that “it is time to focus our nation building here at home.” He stood by while slaughter unfolded in Syria and Russia annexed Crimea. But at least Obama still believed in the basic principles of U.S. leadership, and, when it came to free trade, he was even willing to buck the protectionist sentiments of his own party.

Trump, by contrast, is an out-and-out isolationist and protectionist. He has launched trade wars with all of our major trade partners; praised dictators and castigated democratic allies; and has either pulled out or has promised to pull out of international agreements such as the Paris climate accord, the Trans-Pacific Partnership and the Iran nuclear deal. Although the United States remains in NATO, Trump has raised uncertainty about whether he would come to the defense of its members. His “America First” mantra — a throwback to the 1930s — suggests that U.S. foreign policy will no longer be based, as it has been since 1945, on support for security alliances and free trade.

As corrosive as Trump’s policies is his personality. He is so erratic and ignorant that he makes dictators such as China’s Xi Jinping look good by comparison. Xi may be presiding over a Big Brother state, but at least he appears to be rational and knowledgeable. Trump’s tweets, by contrast, often sound deranged. His actions frequently make as little sense as his words. Typical is the way he flip-flopped on Syria, announcing a total withdrawal of U.S. forces in December before now deciding to keep 1,000 troops.

If you’re an ally of the United States, how can you entrust your security to a superpower that seems to have lost its marbles? If Americans could elect Trump, what kind of demagogue will we choose in the future? We are fast losing the global confidence needed to maintain our global power. A shocking Pew Research Center poll last year found that far more people around the world view the United States as a threat than China or Russia. That perception is a bigger blow to U.S. primacy than any new weapons system that China or Russia could develop.

We are also losing backing at home for U.S. leadership abroad. Although a Chicago Council on Global Affairs survey finds that 70 percent of respondents support an “active part in world affairs,” leading Democrats sure aren’t acting like it. Though they revile Trump, many are in sympathy with his isolationist and protectionist instincts. Progressives even attack Trump for being too activist in Venezuela, while congressional Democrats are blocking ratification of the renegotiated North American Free Trade Agreement because they view it as too pro-trade. Republicans used to be the party of free trade and a hawkish foreign policy, but under Trump, those have become minority sentiments.

We may still see a snapback to a normal U.S. foreign policy after Trump is gone — but I wouldn’t count on it. This may be, gulp, the new normal. And that’s bad news for the world, because if America doesn’t underwrite global security, no one else will. The likely result will be a new global disorder where everyone pursues a “me first” policy and no one looks out for the common good.

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