Nuclear non-proliferation treaty

Treaty on the Non-Proliferation of Nuclear Weapons

The NPT linked restrictions on nuclear weapons to peaceful nuclear cooperation and a commitment to disarmament.

When: 1968–1970 and subsequent implementation
Where: Worldwide

A later map of participation in the Nuclear Non-Proliferation Treaty; colours distinguish forms of participation.

The NPT linked restrictions on nuclear weapons to peaceful nuclear cooperation and a commitment to disarmament.

Background

A world already divided by nuclear possession

By the 1960s, the nuclear arms race raised fears that many more states would acquire weapons. Negotiations sought to limit that spread while addressing demands for peaceful nuclear technology. The resulting agreement distinguished states that already possessed nuclear weapons from those that did not.^[1]

What happened

1968–1970
Signature and entry into force
The treaty opened for signature in 1968 and entered into force on 5 March 1970. Non-nuclear-weapon parties undertook not to acquire weapons, with safeguards supporting verification. Nuclear-weapon parties accepted obligations against transferring weapons or assisting their acquisition.^[2]

Impact & evidence

The wider bargain

Disarmament is part of the treaty

Article VI commits parties to pursue negotiations in good faith on nuclear disarmament. Peaceful nuclear cooperation is another central element. Describing the NPT only as a prohibition directed at non-nuclear states leaves out these reciprocal commitments and the disputes over whether they have been fulfilled.^[2]

Aftermath & legacy

A framework with enduring tensions

The treaty became central to non-proliferation diplomacy without producing a nuclear-free world. Its unequal recognition of nuclear possession and the pace of disarmament remain contested. Assessing its significance requires distinguishing the spread it may have constrained from the arsenals and security inequalities it has not eliminated.^[3]

Sources & image credits (3)

File:NPT Participation.svg : Allstar86 , L.tak , Danlaycock derivative work: Danlaycock Image source ↗