When was the Nuclear Non-Proliferation Treaty opened for signature and what are its essential features?
On 1 July 1968 the Nuclear Non-Proliferation Treaty—or NPT for short—was opened for signature. It was signed that same day by the United States, the United Kingdom, the Soviet Union and 58 other countries.
The Treaty defined nuclear weapon States (NWS) as those five countries that tested nuclear weapons before 1968: that is, China, France, the Soviet Union, the United Kingdom and the United States—and defined all others as non-nuclear weapon States (NNWS).
The NPT is built upon three “pillars”: nuclear non-proliferation, nuclear disarmament and the peaceful use of nuclear energy. It is also based upon a so-called “grand bargain”; namely, that the non-nuclear weapon states agreed not to develop nuclear weapons, and in return the nuclear-weapon states agreed to disarm their nuclear weapons. The non-nuclear weapon states would also receive assistance in developing nuclear power for peaceful purposes.