The Trump administration’s detention of a green-card holder who was a leader in the Columbia University protests against Israel has put a face on the debate over immigration and the limits of free speech, with a sympathetic twist: The man, Mahmoud Khalil, is married to an American, and they are expecting their first child next month.

Appeals to Khalil’s free speech rights are meritless. A green card is not synonymous with citizenship, though many seem to believe otherwise. Indeed, the federal government has the power to revoke a green card at any time, consistent with its statutory authority and assuming due process.

Mahmoud Khalil, a former graduate student, is now detained by Immigration and Customs Enforcement and faces deportation.