“The China shock on large-scale manufacturing and its mass employment effects, that part is largely behind us,” Mr. Autor said. Now, the challenge is Chinese competition on more technologically complex products, like automobiles, airplanes or microprocessors. The manufacturing of more labor-intensive, less technologically complex products like apparel is migrating to lower-wage countries like Bangladesh and Ethiopia.

But a shift in where certain products are made is different from a net increase in the level of global connectivity. The level of economic integration is remaining level, even as the details of exactly what is made in which country are changing.

“I don’t think there’s any turning back the clock,” Mr. Autor said, referring to a return to a world where less technologically complex and more labor-intensive products are again made in the United States. “I think we should be girding ourselves for the real challenge, which is struggles over intellectual property and frontier industries.”

The Trump administration’s efforts to pressure China, if they succeed, would do some of that. But those actions have been paired with tariffs on steel and aluminum that appear more aimed at protecting American manufacturing of the metals. The administration’s approach could backfire if it unleashes a series of escalating tit-for-tat tariffs on all sorts of goods, undermining global commerce without fixing the underlying problems in information-intensive industries.

If the latest trade skirmishes do blow up into a trade war, those new barriers to international commerce might also block a long-predicted reward of globalization: a new world of customers. The rise in global economic integration, for all the disruption it has meant for certain workers in the United States and Western Europe, has also been a story of hundreds of millions of people becoming more connected to the worldwide economy, and achieving higher standards of living in the process.

Homi Kharas, a senior fellow at the Brookings Institution, studies the rise of the global middle class — which in his calculations includes people with income of at least $10 per person per day in 2005 dollars. For a family of four, adjusted to 2018 dollars, that works out to around $19,000 a year.

In 1990, only 23 percent of the world’s population fit that category. Today 45 percent do, meaning an additional 2.3 billion humans are now able to afford the luxuries that the global economy provides: abundant food, motorized transportation, mobile phones and the like.