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Nuclear Non-Proliferation Treaty (NPT)

History Page Type:
Monday, June 6, 2016
President Lyndon Johnson looking on as Secretary of State Dean Rusk prepares to sign the NPT, 1 July 1968. Photo Courtesy of the Lyndon B. Johnson Presidential Library.

The Nuclear Non-Proliferation Treaty (NPT) is a comprehensive international arms control agreement addressing both horizontal and vertical nuclear proliferation.

Negotiated and signed under President Lyndon B. Johnson, the NPT opened for signature on July 1, 1968. It was later ratified by the Senate under President Nixon and entered into force on March 5, 1970. Glenn Seaborg, a nuclear chemist during the Manhattan Project and Chairman of the US Atomic Energy Commission (AEC) from 1961-1971, was instrumental in the treaty’s negotiations. He and the AEC worked to ensure the NPT included safeguards, such as International Atomic Energy Agency (IAEA) on-site inspections, to verify countries’ compliance and use of nuclear material for peaceful civilian programs as opposed to nuclear weapons.

The treaty is premised upon a fundamental bargain between nuclear states, then recognized as the United States, Russia, the United Kingdom, France, and China, and nonnuclear states. Former U.S. ambassador and arm-control expert Thomas Graham Jr. explains, “The treaty included a basic bargain whereby the non-nuclear weapon states agreed to foreswear nuclear weapons in exchange for unfettered access to the peaceful benefits of nuclear energy and a pledge from nuclear weapons states to eventually eliminate their nuclear arsenals.” Non-nuclear states thereby agreed to never develop or acquire nuclear weapons and to submit to international inspections of nuclear facilities in exchange for a concerted effort by nuclear powers to limit, reduce, and ultimately eliminate their stockpiles. Additionally, nuclear states agreed to assist countries develop civilian nuclear programs for peaceful purposes and forgo transferring nuclear weapons to other non-nuclear states.

The NPT can be considered among the successes of détente, in which the United States and Soviet Union, the world’s two principal nuclear powers, cooperated to slow the rate of international nuclear proliferation, limit escalation of the ongoing Cold War arms race, and ultimately work towards complete nuclear disarmament. Historian Richard Rhodes in Arsenals of Folly writes that the treaty “put the five nuclear powers on notice that the rest of the world would not tolerate the presence of their menacing nuclear arsenals forever.”

Ambassador Graham observes, “Maintaining both ends of this central bargain is vitally important to the long-term viability of the NPT.” This has proven to be quite difficult to achieve. While the majority of UN member states have signed the treaty, India, Israel, Pakistan, and South Sudan have refrained from doing so. The first three are known to have nuclear weapons programs. Furthermore, North Korea withdrew from the NPT on January 10, 2003 and has since tested several nuclear devices.

Nevertheless, progress has been made to reduce nuclear proliferation since the NPT’s ratification. For example, on May 11, 1995 at the Review Conference on New York City, the signatories agreed to extend the treaty indefinitely. This decision demonstrated the international community’s ongoing commitment to nuclear nonproliferation.

Siegfried Hecker, an American scientist who served as director of Los Alamos National Laboratory from 1986 to 1997, recalls that at the time of 1995 renewal of the NPT American government officials “were taking a lot of flak from the non-nuclear power countries. ‘When are you guys going to stop testing? After all, the eventual goal was to eliminate nuclear weapons.’” As a result of this mounting pressure from non-nuclear states, the 1995 extension of the NPT served as an impetus for the Comprehensive Test Ban Treaty (CTBT), which opened for signature the following year on September 24, 1996. The CTBT calls for zero yield from nuclear weapons and bans nuclear testing. However, as not enough countries have ratified it, the CTBT has yet to enter into force.

Nuclear Nonproliferation and the NPT Today

Shortly after assuming office, President Obama delivered an address in Prague on April 5, 2009 in which he made nuclear arms reduction a central goal of his administration. He stated:

If we believe that the spread of nuclear weapons is inevitable, then in some way we are admitting to ourselves that the use of nuclear weapons is inevitable…As the only nuclear power to have used a nuclear weapon, the United States has a moral responsibility to act. We cannot succeed in this endeavor alone, but we can lead it, we can start it. So today, I state clearly and with conviction America’s commitment to seek the peace and security of a world without nuclear weapons.

President Obama’s efforts to adhere to the NPT and reduce America’s nuclear arsenal were reflected in the New Strategic Arms Reduction Treaty (START), signed in Prague between the US and Russia a year later on April 8, 2010. The agreement, calling for both arms reduction and limitations, entered into effect on February 5, 2011 and replaced the Strategic Offensive Reductions Treaty (SORT).

Within seven years, by February 5, 2018, both countries agreed to reduce the number of offensive weapons with a 30% reduction in deployed strategic warheads and 50% reduction in ICBMs and ICBM launchers. The two also pledged to continue to submit to international inspections for verification.

The US Department of State acknowledges that the agreement does not impose limitations on missile defense and conventional strike capabilities, noting in particular that it “does not limit testing, development, or deployment of current or planned U.S. missile defense programs or long-range conventional strike capabilities.”

2018 marks 50 years since the NPT was first signed. Many non-nuclear states remain frustrated by the nuclear powers’ failure to eliminate their stockpiles. After a campaign led by non-governmental organizations and many non-nuclear states, the United Nations General Assembly approved the Treaty on the Prohibition of Nuclear Weapons in 2017. The new treaty bans the use, possession, development, testing, and transfer of nuclear weapons.

Many critics point to the thousands of nuclear weapons still deployed around the world and North Korea, Israel, India, and Pakistan’s nuclear programs as evidence of the NPT’s shortcomings. Yet Seaborg argued in a 1986 interview that on balance the NPT “had a tremendous influence in slowing the proliferation of weapons. Whereas if there were no NPT…it’d just be a plethora of countries that were building nuclear weapons. Now there are obviously a few countries that haven’t signed the NPT and are still problems. But it’s much better to have it focused down to a few countries than to have dozens of countries going the direction of nuclear weapons.”

Although universal compliance on nuclear test bans and treaties, as with most international law, is difficult and highly unlikely, nuclear nonproliferation and disarmament are likely to remain goals of the international community as long as nuclear weapons pose a threat to international peace and security.

For more information about proliferation, visit our article on nuclear proliferation today.