For most of the 20th century, the center of gravity in science was anywhere but the US. On the eve of World War II, the great laboratories were in Europe, and American research — especially in physics — was widely seen as trailing them.

Then came the “scientific exodus”: Foreign refugees from fascism — like Einstein, Fermi, Bethe, Szilard, von Neumann, and others — remade US science. One reason we won the war is because America collected foreign talent while its enemies expelled it. And Washington locked in that advantage postwar by building Vannevar Bush’s vision of federally funded university science, which turned the country into a scientific superpower, leaving the rest of the world as one big talent pool.

Eight decades later, the US has started turning off that spigot. In June, the Trump administration suspended or curtailed visas from 19 countries, explicitly hitting student and exchange categories. This spring, it even terminated thousands of student SEVIS records — the official Department of Homeland Security status files for international students — before reversing course under legal pressure. August arrival records showed a roughly 19 percent year-over-year drop in new international student entries. That represented the biggest non-pandemic decline on record, even as surveys showed top researchers planning to leave the US in droves.

For an economy that runs on scientific innovation, this is a self-own of historic levels

So, here’s the (measured) good news: Despite what appears to be the Trump administration’s best efforts, new federal data reported by Nature shows that international PhD numbers are essentially flat year over year. That’s not a triumph, but it’s not the crash many feared — not yet — and it buys time to mount the political resistance needed to keep America’s foreign talent engine running.

A resilient system… for now

It’s important to understand that, in the fields that power the technological frontier — computer science, engineering, math — international students are not a rounding error; they are the majority of new US PhDs. In 2023, temporary-visa holders earned 62 percent of computer and information sciences doctorates, 56 percent of engineering PhDs, and 53 percent of math and statistics doctorates.

And contrary to arguments that the US is educating foreign students only to see them take their talents elsewhere, many of those researchers stick around. Roughly three-quarters of international science and engineering PhDs from the 2017–2019 cohorts were still in the US five years later. Keep the pipeline open, and the US keeps the labs, grants, and startup ecosystem that rely on them humming. Close it, and we’ll feel the loss in capacity, not just headcount.

Perhaps you’re thinking that, if the US restricts foreign students, more seats will go to American-born candidates. But we don’t have enough of those candidates.

While more US citizens and permanent residents have been pursuing and attaining science, technology, engineering, and mathematics (STEM) degrees over the past decade, the growth in graduate degrees has been uneven, including a 3 percent year-over-year dip in 2022. Far too many American students aren’t ready to take those places. 15-year-olds in the US scored below 25 other international education systems in math, while only 15 percent of ACT-tested high school graduates met the standardized test’s STEM readiness benchmark in 2023.

If every foreign student in STEM left the US tomorrow, we would barely have a STEM sector. Compare that to China, which is already minting nearly twice the number of STEM PhDs as the US and doing it almost entirely with domestic talent. Yes, China has four times the population, but that’s partially the point. To compete, America can’t only rely on its own resources.

Made in the USA

You can see the downstream payoff of foreign scientific talent everywhere innovation is actually measured. Immigrants produce about 23 percent of US patents — far above their share of the population — and their patents are, on average, at least as influential when judged by citations and market value.

Those discoveries transform into prosperity. Forty-six percent of the companies in the current Fortune 500 were founded by an immigrant or the child of one. In the startup economy, immigrants have founded 55 percent of US “unicorns” (billion-dollar startups), while a large majority of top private AI firms have at least one immigrant founder. A nontrivial share of those founders first came as international students. The country’s most dynamic sectors — chips, AI, biotech — are the ones that lean hardest on global talent. Just ask Jensen Huang, the Taiwan-born founder of the AI chip firm Nvidia, who came to the US as a 9-year-old and now runs the most valuable company in the world.

The same pattern shows up at the very top of the scientific pyramid. Since 2000, immigrants have won roughly 40 percent of the Nobel Prizes awarded to Americans in physics, chemistry, and physiology or medicine. This year, both Jordan-born Omar Mwannes Yaghi, who moved to the US at 9, and Netherlands-born Joel Mokyr, who came to America as a grad student, added to that list. These wins aren’t a coincidence; it’s what happens when a research system reliably attracts and retains the world’s best.

So, the fact that international student enrollment is holding steady for now is reassuring — but only if we take advantage of it. The United States became a scientific superpower by building great labs and then keeping the doors open to the people who wanted to work in them. If we keep that promise — stable study-to-work pathways, predictable visa processing, no sudden rule changes — the evidence suggests those researchers will come, contribute disproportionately to scientific discoveries and new business ventures, and, in many cases, stay.

If we don’t, the losses will show up exactly where we can least afford them: fewer grant-winning teams, fewer breakthrough patents, fewer deep-tech startups, fewer laureates, and a country that goes from leading to following.

A version of this story originally appeared in the Good News newsletter. Sign up here!