The Trump administration has been clear about the motivation for cracking down on foreign students: it is a question of national security.

Dozens of foreign students, with valid visas or Green Cards, have been swept up because of their support for pro-Palestinian causes.

Deportation proceedings have focused on the power of the secretary of state to decide whether the person’s presence on American soil would have “serious adverse foreign policy consequences”.

Last week, the administration took aim at another set of students. Marco Rubio, the secretary of state, announced he would “aggressively revoke” the visas of Chinese students, including those with links to the Chinese Communist Party or who were studying sensitive subjects.

National security powers 

That idea had been laid out in Project 2025, a blueprint drawn up by conservatives to kickstart Donald Trump’s presidency.

And it is a familiar strategy. The White House has frequently cited national security powers as the president pushed through new policies and regulations without having to resort to the long-winded and uncertain passage of legislation through Congress.

In the same way, Mr Trump and his allies used questions of national security for his “liberation day” tariffs, ramping up duties on imports.

In that case, the tariffs are designed to rebalance what Mr Trump views as unfair trade practices, reduce US dependence on foreign products and to bring manufacturing jobs back home.

In the same way, listen closely and Mr Trump and his vice-president have made no secret of their “America First” plan for universities that goes beyond questions of national security.

In the Oval Office last week, Mr Trump suggested a cap on the number of foreign students at Harvard University.

“We have people who want to go to Harvard and other schools they can’t get in because we have foreign students there,” he said.