ROBERT SIEGEL, HOST:
President Trump signed paperwork today formally pulling the U.S. out of a 12-nation trade deal that the Obama administration had negotiated.
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PRESIDENT DONALD TRUMP: Great thing for the American worker, what we just did.
SIEGEL: Congress had already refused to ratify the Trans-Pacific Partnership, making Trump's withdrawal largely symbolic. But it's also a signal of the new president's nationalistic ideology. If Trump continues down that path, it would represent a sharp break with more than seven decades of U.S. foreign policy. NPR's Scott Horsley reports.
SCOTT HORSLEY, BYLINE: Moments after he took the oath of office last Friday, President Trump announced what he called a new vision, one that he wanted heard in every city and every foreign capital.
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TRUMP: From this day forward, it's going to be only America first - America first.
HORSLEY: Foreign policy expert Daniel Drezner of the Fletcher School of Law and Diplomacy says when Trump spoke those words, he heard the end of the international order that America has been working to build ever since World War II.
DANIEL DREZNER: The key word in that speech was only - America first. All presidents try to seek to advance the national interest. But Trump was explicitly saying we don't care if anyone else benefits. All we care about is if we benefit.
HORSLEY: The word only was not in Trump's prepared remarks. He added it at the last minute. But it's consistent with the view Trump often expressed during the campaign. The new president sees foreign policy as just another business transaction, and he believes America has been getting a raw deal.
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TRUMP: For many decades, we've enriched foreign industry at the expense of American industry, subsidized the armies of other countries while allowing for the very sad depletion of our military.
HORSLEY: Critics say Trump is viewing American interests through a too-narrow lens. From the Marshall Plan to NATO and the World Trade Organization, the U.S. has worked to promote peace and prosperity around the globe. But Matthew Slaughter, who worked in the Bush administration and now serves as dean of the Tuck business school at Dartmouth, says America didn't make those investments out of charity.
MATTHEW SLAUGHTER: There was clearly enlightened self-interest. It was to help make our country more secure, and it was to help grow good jobs at good wages.
HORSLEY: Supporters of that international order say it's worked around the world as well. It's lifted billions of people out of poverty, helped to combat infectious disease and prevented a third world war. But even defenders can see that order is being tested in the U.S. and elsewhere, especially by those who feel they haven't adequately shared in the fruits of globalization. Economic nationalism was a fringe movement in the U.S. when Pat Buchanan pushed it 20 years ago. Now Buchanan says it's put Donald Trump in the White House.
PAT BUCHANAN: He's speaking both for and to the Middle Americans who have been left out and left behind.
HORSLEY: Not everyone, even in Trump's own Cabinet, shares the president's narrow definition of American interests. Defense Secretary James Mattis, for example, has defended U.S. participation in NATO as enormously beneficial to this country's own national security. Dartmouth's Slaughter is waiting to see whether foreign policy in the Trump administration is actually guided by Mattis' brand of global bridge-building or the more populist wall-building of the president's inaugural address.
SLAUGHTER: That's the $64,000 question. All Americans are trying to understand how that narrative, which was remarkably dark - what that translates into in terms of policy, no one really knows.
HORSLEY: Slaughter says supporters of the international order have a limited window to find genuine answers to the populist backlash in the U.S. and elsewhere. Meanwhile, if America turns inward, as suggested by its withdrawal from the Asia Pacific trade deal, China is more than ready to take up the slack.
Scott Horsley, NPR News, Washington.