Fact Sheet
Bureau of Arms Control, Verification and Compliance
September 1, 2011


[This fact sheet has been updated; see current version.]

The United States will be more secure by ratifying the Comprehensive Nuclear Test-Ban Treaty (CTBT), which establishes a global legal ban on the explosive testing of nuclear weapons.

The CTBT Helps Restrain Further Nuclear Weapons Proliferation.

It is in our national security interest to prevent other states from advancing their nuclear weapon capabilities, an objective that would be reinforced through the adoption and entry into force of the global, legally binding CTBT. With a global ban on nuclear explosive tests, states interested in pursuing or advancing their nuclear weapons programs would have to either risk deploying weapons uncertain of their effectiveness or face international condemnation and possible sanctions for conducting nuclear tests.

With or without nuclear explosive testing, it is possible for states to develop fission weapons, but without testing there would always be uncertainty how well they would perform. A ban on nuclear explosive testing will prevent more established nuclear weapon states from confirming the performance of more advanced nuclear weapon designs that have not been successfully tested in the past.

The United States possesses the most extensively tested and certified nuclear arsenal in the world and remains the world’s pre-eminent conventional weapons superpower. Our nation has been able to maintain military superiority while also observing a unilateral testing moratorium for almost twenty years, thus abiding by the core prohibition of the CTBT. Yet, the absence of U.S. ratification of the Treaty continues to limit our ability to promote a global ban.

Ratification of the CTBT Is Part of an Integrated Nuclear Security Strategy.

The President has identified the spread of nuclear weapons to terrorists or other states as a direct and pressing threat to American security and has provided unprecedented resources – financial, political and technical – to prevent proliferation. Since entering office, the Administration has achieved entry into force of the New START Treaty, released an updated Nuclear Posture Review, and helped to achieve the consensus Action Plan at the 2010 Nuclear Non-Proliferation Treaty (NPT) Review Conference.

The Administration has also convened the successful 2010 Nuclear Security Summit, helped secure and relocate vulnerable nuclear materials, led efforts to establish an international nuclear fuel bank, and increased effective multilateral sanctions against both Iran and North Korea for their illicit nuclear activities.

Support for and pursuit of CTBT ratification is another key element of this strategy to strengthen America’s security. Ratification of the Treaty would likely bring additional international support for carrying out other elements of the Action Plan from the 2010 NPT Review Conference.

The CTBT Can Be Verified.

At the heart of the CTBT’s verification regime is an international monitoring system that includes hundreds of sensors deployed around the world, which will help the United States and other CTBT Parties verify compliance with the Treaty. This system has already detected the two nuclear explosive tests conducted by North Korea; its capabilities will continue to improve as the system is completed.

Entry into force also will bring to bear the option for an on-site inspection, which will help clarify ambiguities regarding a possible nuclear test. Taken as a whole, the Treaty’s robust verification regime, which supplements our state of the art monitoring national technical means capabilities, will make it extremely difficult for any state to conduct militarily significant explosive nuclear tests that escape detection.

The United States Does Not Need to Conduct Nuclear Tests.

President Obama said in April 2009, “As long as [nuclear] weapons exist, the United States will maintain a safe, secure and effective arsenal to deter any adversary, and guarantee that defense to our allies.”

U.S. nuclear weapons are now maintained without explosive nuclear testing. From 1945-1992, the United States conducted 1054 nuclear explosive tests, more than any other country. Since it adopted a moratorium on nuclear explosive testing in 1992, the United States has maintained the reliability of our arsenal through an extensive and rigorous stockpile stewardship program that includes surveillance and warhead life extension programs. This Administration has committed more than $85 billion in funding over the next decade, to maintain the U.S. stockpile, a modern nuclear weapons production complex, and a highly trained and exercised base of nuclear experts, engineers, and technicians.

For over 15 years, the Secretaries of Defense and Energy from Democratic and Republican administrations, and the directors of the nuclear weapons laboratories have annually assessed our arsenal to be safe, secure and effective, and each year they have determined that we do not need to conduct explosive nuclear tests.