Treason

Three out of the five kinds of spies listed by Sun Tzu in The Art of War are members of the enemy. To run a spy in foreign territory is to incite, condone, and benefit from treason. Treason presents one of the most serious ethical challenges to espionage and counter-intelligence operations. The chapter provides an account of the accusation of treason—of what a treasonous act consists in, and why it is presumptively wrongful. It then shows that treason is sometimes morally permissible in principle, indeed mandatory—not merely between enemies but also between declared allies, and not merely at the behest of just foreign actors but also at the behest of unjust foreign actors. The final section tackles the complex question of traitors’ acts of personal betrayal vis-à-vis their friends, relatives, and colleagues.