To begin with, universities should not be intimidated by the claim that public opinion is turning against them. That’s not necessarily true

Less than two months in office, the Trump administration has conclusively demonstrated two things: if it declares you an enemy, it will come after you; and when it comes after you, it will test the limits of legality.

JD Vance already professed years ago that professors are the enemy in his view. And the president himself is encouraging his underlings to adopt the strategy familiar from his decades in business: do something illegal and see if anyone sues. It is crucial that university leaders see the measures taken against Columbia not as an isolated incident, but as a test for how far the education system can be subjugated. In other words, it is not an isolated problem for one place but a collective challenge that requires a collective response.

Jan-Werner Müller is a Guardian US columnist and a professor of politics at Princeton University.