The war with Iran has defense experts wondering if Khamenei will attempt to activate sleeper cells on U.S. soil

“We know where most of them are. We got our eye on all of them, I think,” President Trump told the world media this week. The commander in chief was speaking about the possibility of Iranian sleeper cells being embedded and activated in the United States.

The concept of sleeper cells—groups of organised, foreign spies living unremarkable lives until directed into action—may, in the public imagination, feel like something from the movies or the pages of a book. The same goes for lone wolves...