Reducing the risks of nuclear weapons and preventing their spread is not only the responsibility of states possessing nuclear weapons. One important approach for states that have foresworn nuclear weapons under the nuclear Nonproliferation Treaty (NPT) is to establish nuclear weapons free zones.
A nuclear-weapon-free zone (NWFZ) is a specified geographical region in which countries commit themselves not to manufacture, acquire, test, or possess nuclear weapons. Within these zones, countries may use nuclear energy for peaceful purposes, with appropriate international safeguards. NWFZs are a way for non-nuclear-weapons states, which have already committed under the NPT not to acquire nuclear weapons, to make additional assurances and commitments to prevent proliferation and reduce the risk they will be used.
Five such zones exist today, encompassing more than 100 countries and covering nearly the entire Southern Hemisphere and beyond: Latin America (the 1967 Treaty of Tlatelolco), the South Pacific (the Treaty of Rarotonga), Southeast Asia (the 1995 Treaty of Bangkok), Africa (the 1996 Treaty of Pelindaba), and Central Asia (the 2006 Treaty of Semipalatinsk). International efforts are underway to create a new weapons of mass destruction free zone in the Middle East, with a UN-sponsored conference to discuss the matter in 2012.
Each NWFZ treaty includes a protocol for the five nuclear-weapon states recognized under the NPT (China, France, Russia, the United Kingdom and the United States) to sign and ratify. These protocols, which are legally binding, call upon the nuclear-weapon states to respect the status of the zones and not to use or threaten to use nuclear weapons against treaty members. Such declarations of non-use of nuclear weapons are referred to as “negative security assurances.”
When it submitted the African and South Pacific nuclear-weapon-free-zone protocols to the Senate, the Obama administration declared that it “will extend the policy of the United States not to use or threaten use of nuclear weapons against regional zone parties” that are members of the NPT in good standing.
The support of the nuclear-armed states for the nuclear-weapon-free-zones helps to promote the principle that states forgoing nuclear weapons are enhancing their security.
The United States is the only country out of the five that has yet to ratify the protocols to the African and South Pacific nuclear-weapon-free-zone treaties. President Bill Clinton signed these protocols in 1996, but they were not submitted to the Senate for ratification until President Barack Obama did so in May 2011. The protocols are considered to be treaties and therefore need a two-thirds Senate majority to support ratification.
None of the nuclear-weapon states has signed the relevant protocol for the Southeast Asia treaty because of concerns that it conflicts with the right of their ships and aircraft to have freedom of movement in international waters and airspace. The other zones do not explicitly rule out the transit of nuclear weapons by nuclear-weapon states through the zones, and the general practice of nuclear-weapon states is not to declare whether nuclear weapons are aboard their vessels.