WASHINGTON, June 9 -- For Americans born in the country, citizenship is a settled fact that no government can reach. For the millions who were naturalized, the Trump administration is working to make it provisional. The Justice Department has moved to revoke the citizenship of 17 naturalized Americans at once, the largest such action it has ever announced, and a marker of how far an exceptional legal tool is being stretched into routine use.

The department said it had filed denaturalization cases in federal district courts around the country against 17 people accused of grave offences, among them the sexual abuse of a minor, wire and bank fraud, and the wholesale distribution of drugs. It packaged the announcement around those crimes, pr...