A Harvard professor and former ambassador to China said a federal judge’s extension of an order that blocks the Trump administration’s attempt to end foreign student enrollment at the university is “a very positive decision.”

“How is it possible for American students to live in the world, prepare to go out in the world, in whatever profession, without any access to foreigners?” Nicholas Burns told Boston Public Radio on Thursday. Burns served as the ambassador to China under President Joe Biden.

“This is a destructive decision by the Trump administration. It’s vengeful. And it’ll ruin all of our universities if it’s carried out,” he said.

Now working at Harvard’s Kennedy School of Government, Burns said he teaches many international students who have told him they are concerned about being able to return to classes in the fall. He said others are shifting plans and not going home over summer break in case they’re not able to re-enter the country.

“I don’t think [President Donald Trump has] won the battle, but he’s certainly put fear into the hearts and minds of our students,” Burns said.

Secretary of State Marco Rubio also announced this week that the administration would “aggressively” revoke Chinese student visas for people with connections to the Chinese Communist Party or studying in “critical fields.”

“The devil’s going to be in the details,” Burns said of Rubio’s announcement.

Burns said he does think students from China should continue to be screened as they have since a proclamation under the first Trump administration in 2020, which denies visas to students with connections to the People’s Liberation Army.

“We don’t want them in this country,” Burns said. “But we can screen for those students, and we do screen effectively for them,” adding that these restrictions continued under Biden.

But the vast majority of Chinese students in the United States — around 277,000 by some estimates — “revel” at being in a democratic society where they are also a benefit to American students, Burns said.

There’s also an economic argument for admitting international students.

“If you look at the number of biotech CEOs in the Boston, Cambridge, Waltham area, tech CEOs in Silicon Valley, a very high percentage are Indian and Chinese Americans. And so they’re adding to our economy. They’re innovating,” Burns said.