What is the fundamental legal obligation of Nuclear Weapon States (NWS) under the Non-Proliferation Treaty (NPT)?

The fundamental legal obligation of Nuclear Weapon States (NWS) under the Non-Proliferation Treaty (NPT), as outlined in Article VI, is to pursue negotiations in good faith on effective measures relating to nuclear disarmament. This obligation entails engaging in serious and sustained efforts to reduce and ultimately eliminate their nuclear arsenals. While the NPT does not specify a timeline or concrete steps for disarmament, it establishes a clear legal commitment for NWS to work towards this goal. The precise interpretation and implementation of Article VI have been subject to debate, but the core principle remains that NWS are legally bound to make progress towards nuclear disarmament. This is a key element of the NPT bargain, in which non-nuclear weapon states agree not to acquire nuclear weapons in exchange for the NWS pursuing disarmament and providing access to peaceful nuclear technology.