25 Years After Comprehensive Test Ban Treaty, Testing Is Taboo


For Immediate Release: Sept. 20, 2021

Media Contacts: Daryl G. Kimball, executive director, (202) 463-8270 ext. 107; Tony Fleming, communications director, (202) 463-8270 ext. 110

(Washington, D.C.)—Today, the Washington-based Arms Control Association hailed the success of the 1996 Comprehensive Test Ban Treaty (CTBT), which opened for signature 25 years ago this week, and called for bolder action by UN member states and the UN Security Council to bolster international support for the global norm against nuclear weapons testing and to push the remaining eight CTBT hold-out states to ratify the treaty.

In events later this week at the United Nations in New York, the international community will mark the 25th anniversary of the treaty, the successful creation and operation the international monitoring system to verify compliance, and the value of a testing halt. A high-level conference will be convened September 23 at UN headquarters, and a special UN Security Council session will convened September 27 by Ireland, which holds the presidency of the Council.

The treaty, which opened for signature Sept. 24, 1996, has near-universal support with 185 signatories, including the five original nuclear testing states. All CTBT states agree that the treaty prohibits “any nuclear weapons test explosion, or any other nuclear explosion” no matter what the explosive yield.

“A quarter century after it was concluded, the 1996 Comprehensive Test Ban Treaty (CTBT) has achieved its core goal: halting nuclear test explosions,” said Daryl G. Kimball, executive director of the Arms Control Association.

Most of the 2,000-plus nuclear test blasts conducted by the world’s nine nuclear-armed states were used to confirm new warhead designs and develop more deadly weapons systems, which in turn fueled a dangerous spiral of global nuclear competition.

Without the option to conduct nuclear tests, it is more difficult, although not impossible, for even the most advanced nuclear states to develop, prove, and field new warhead designs. The CTBT is a powerful brake on vertical and horizontal nuclear proliferation.

“The CTBT has effectively put an end to militarily significant nuclear test blasts. Today, even those nuclear-armed states that have not signed or not ratified the CTBT, including India, Israel, and Pakistan, observe nuclear testing moratoriums. Only one country has conducted nuclear test explosions in this century, and even that country—North Korea—halted nuclear testing in 2017,” noted Kimball, who has campaigned for a global testing halt for more than 30 years.

However, because of the treaty's onerous entry-into-force requirement and the failure of eight key states, including the United States and China, to ratify, the treaty has not entered into force. Among other challenges, this means the treaty’s short-notice on-site inspection tools cannot yet be used.

"President Joe Biden, a longtime CTBT advocate, should clearly reaffirm U.S. support for the treaty and its entry into force," Kimball said.

In 2020, then-candidate Biden said: “We have not tested a [nuclear] device since 1992, we don’t need to do so now. A resumption of testing is more likely to prompt other countries to resume militarily significant nuclear testing and undermine our nuclear nonproliferation goals.”

“We cannot afford to take the non-testing norm for granted. To keep a de facto global nuclear test moratorium intact and make headway toward the formal entry into force of the treaty, friends of the CTBT will need to do more than make speeches. Key states will need to rejuvenate their efforts to achieve its entry into force and reinforce the taboo against nuclear testing,” Kimball urged.

“We call on:

  • all UN Security Council Members, including India, to reaffirm their support for a halt to all nuclear testing and pledge to act against violators. Those that have not yet ratified, should explain the status of their ratification efforts.
  • States-parties to the upcoming nuclear Nonproliferation Treaty (NPT) Review Conference should agree to demand that any state that has conducted a nuclear test explosion should seek to initiate their ratification process by 2025.
  • the United States, Russia, and China, each of which continue activities at their test sites, to agree to adopt additional voluntary measures designed to detect and deter possible low-level, clandestine nuclear testing prior to entry into force.”

The last time the Security Council most addressed the issue of the Comprehensive Nuclear-Test-Ban Treaty was on Sept. 22, 2016, marking the 20th anniversary of the Treaty, adopting Security Council Resolution (2310).

“Keeping the door shut on nuclear testing requires leadership and action on the CTBT. It is in every country’s interest to take action to bring the treaty into force, to strengthen the taboo against nuclear testing, and to fully support the work of the CTBT Organization in Vienna,” Kimball said.