Introduction: Asia-Pacific perspectives on no-first use of nuclear weapons

On 22 January 2021, the first legally binding international agreement to comprehensively prohibit nuclear weapons entered into force. The agreement, known as the Treaty on the Prohibition of Nuclear Weapons (TPNW, or “Ban Treaty”) is an important step on the long road to the elimination of nuclear weapons, an expression of solidarity toward that goal. But the Treaty has been roundly rejected by the world’s nuclear-armed states, which claim it will never become part of customary international law due to their persistent objector status, and which continue to value nuclear weapons as security providers in a world of changing power dynamics and strategic uncertainties. This rejection severely limits the Treaty’s impact: regardless of the Treaty’s other strengths and weaknesses, for as long as the nuclear weapons possessors and their nuclear-dependent allies refuse to accept its prohibitions, it cannot play a practical role in taking disarmament forward.