The Russian regime is tyrannical, criminal, murderous, and every bit as paranoid and predatory as its predecessor, the Soviet Union. It thinks the West duplicitous, arrogant and greedy and it wants our secrets, whether military, business or political. To get them it uses an underground army of spies based here, whose most potent weapon is their ordinariness. They are the kind of people you might meet at the school gates, work alongside in an office or see mowing the lawn next door, stealthily penetrating our society. That Russia runs such agents in the U.S., Britain and Europe (and elsewhere) should...