Nuclear nonproliferation kept nine nations from becoming 20+ armed powers—can the same framework prevent AI catastrophe as Trump and Xi meet? David Sanger explains why the Cold War model offers our only template for managing artificial intelligence, but warns the technology moves faster and faces radically different obstacles. The Nuclear Nonproliferation Treaty, signed in 1968, successfully limited nuclear weapons to nine states when Kennedy feared 15-20 nations would have them by the 1970s, demonstrating that voluntary restraint on dangerous technology is historically possible.