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January 19, 2011
Comprehensive Test Ban Treaty (CTBT)

Marking the 60th Anniversary of the Castle Bravo Nuclear Test



Sixty Years Later, Effects of "Castle Bravo" Nuclear Test Linger
Arms Control Today
Essay Looks Back on U.S. Testing in the Marshall Islands

For Immediate Release: February 26, 2014
Media Contacts: Daryl G. Kimball, Executive Director, 202-463-8270, ext. 107; April Brown, Marshallese Educational Initiative, 479-856-6122.

(Washington, D.C.) March 1 is the anniversary of one of the most controversial and harmful of the United States' 1,030 nuclear weapons test explosions: the 15-megaton atmospheric thermonuclear shot code-named "Castle Bravo" over Bikini Atoll in the Marshall Islands.

Six decades later, the Castle Bravo test and the other U.S. nuclear test detonations conducted in the Marshall Islands from 1946 to 1958 have cast a long shadow over the Marshallese people, according to April L. Brown in her article in the March issue of Arms Control Today, "No Promised Land: The Shared Legacy of the Castle Bravo Nuclear Test."

The Bravo Castle test was the largest ever by the United States. It vaporized three islands, created a mushroom cloud that rose to 130,000 feet and spread more than 25 miles in diameter in less than 10 minutes, and spewed radioactive fallout over nearby inhabited islands, including Ailinginae, Rongelap, and Utrik, as well as the Japanese fishing vessel Lucky Dragon.

The order was given "to proceed with the test as planned despite the likelihood that winds would carry the fallout over inhabited atolls," Brown notes. U.S. authorities failed to evacuate the populations for days. Brown recounts how the relocated populations suffered for years afterward and have struggled to obtain better medical treatment and economic assistance from the U.S. government.

In 1994, Brown notes, a U.S. government nuclear declassification initiative revealed that the Rongelapese were for many years the test subjects in a U.S. government-sponsored study on the health consequences of radiation exposures and the Department of Energy believed that fallout from the tests affected a far larger area and more people than officially acknowledged.

"Today, nuclear issues remain at the center of the complex geopolitical relationship between the United States and the Marshall Islands," writes Brown in Arms Control Today. "The Marshallese on the islands suffer from health issues, including high cancer rates and the highest rate of diabetes in the world, and high unemployment," she notes.

"The Marshallese who have relocated to the United States continue to struggle as well. Like the Marshallese who have remained in the islands, the U.S. community suffers from high rates of diabetes and cancer, and it lacks adequate access to medical resources," Brown writes.

Brown is a professor of history at Northwest Arkansas Community College and is co-founder and executive director of the Marshallese Educational Initiative based in Arkansas, where the second-largest concentration of Marshallese reside.

Ceremonies will be held this week to mark the events of March 1, 1954 at the Clinton Presidential Library in Little Rock, Arkansas (Feb. 28) and in the Marshall Islands (Feb. 24-March 1).

To help raise awareness and understanding of the devastating effects of nuclear weapons testing in the Pacific and elsewhere around the globe, Brown's article, "No Promised Land: The Shared Legacy of the Castle Bravo Nuclear Test," is now available online in PDF form.


The Arms Control Association is an independent, membership-based organization dedicated to providing authoritative information and practical policy solutions to address the threats posed by the world's most dangerous weapons. ACA sponsors the Project for the CTBT, which brings together experts and NGOs in support of the entry into force of the 1996 Comprehensive Nuclear Test Ban Treaty


(Washington, D.C.) March 1 is the anniversary of one of the most controversial and harmful of the United States' 1,030 nuclear weapons test explosions: the 15-megaton atmospheric thermonuclear shot code-named "Castle Bravo" over Bikini Atoll in the Marshall Islands.

Week Ahead Feb. 24-March 2: Castle Bravo Test Anniversary; Pentagon Budget; NATO Ministers & G8 Partnership Meetings

In the coming days, the staff and editors at the Arms Control Association will be keeping an eye on the following arms control-related developments. For more news and analysis on these and other weapons-related security issues, consider subscribing to ACA's monthly journal Arms Control Today, which is available in print/digital and digital-only editions. More information and timely analysis is available from www.armscontrol.org. - the Editors at Arms Control Today March 1: 60th Anniversary of the"Castle Bravo" Nuclear Test in the Pacific Ceremonies held this week in Little Rock, Arkansas and...

CTBTO Announces Pledges to Limit Xenon

Tom Z. Collina

The Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) announced Nov. 13 that four medical isotope makers have pledged to reduce radioxenon emissions, a step that the organization said would help it in its mission of identifying nuclear test explosions.

The producers also have agreed to share information on emission levels, the CTBTO said in the announcement.

The increasing global production of medical isotopes has led to higher emissions of the radioactive noble gas xenon, the CTBTO said, and could affect one of the CTBTO’s key verification technologies by masking a potential xenon release from an underground nuclear test. CTBTO Executive Secretary Lassina Zerbo said the cooperation with the medical isotope producers “helps us to provide confidence to our member states that, now and in the future, no radioactive release from a nuclear test will go unnoticed.”

The four companies that signed the pledge are the Australian Nuclear Science and Technology Organisation, Coquí RadioPharmaceuticals Corp. in the United States, the Korea Atomic Energy Research Institute, and PT Batan Teknologi Company Indonesia. The CTBTO will assist producers in clarifying any concerns due to elevated xenon levels.

The Belgian-based Institute for Radio Elements signed the pledge in June.

The agreement was signed during a workshop at the CTBTO’s Vienna headquarters on the radioactive signatures of medical and industrial isotope production. The permanent representatives to the UN office in Vienna of Belgium, Indonesia, South Korea, and the United States attended the ceremony, along with 70 representatives from established and prospective producers of medical isotopes from 24 countries and representatives from the International Atomic Energy Agency.

The Comprehensive Test Ban Treaty (CTBT) bans all nuclear explosions in the atmosphere, in outer space, underwater, and underground. The CTBTO’s global verification regime, which is to have 337 facilities when it is fully operational, monitors the globe for nuclear explosions. Once the CTBT has entered into force, on-site inspections can also be used to search for evidence of a nuclear explosion.

The Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) announced Nov. 13 that four medical isotope makers have pledged to reduce radioxenon emissions, a step that the organization said would help it in its mission of identifying nuclear test explosions.

Foreign Ministers Urge Action on CTBT

Daryl G. Kimball

More than 50 foreign ministers and senior government representatives met Sept. 27 at the United Nations to call for prompt action toward entry into force of the 1996 Comprehensive Test Ban Treaty (CTBT).

One hundred eighty-three states have signed the treaty, and 161 have ratified it. But under the terms of the treaty, eight more listed in Article XIV of the treaty, including the United States and China, must ratify it to achieve entry into force.

This year’s conference on facilitating entry into force, the eighth such meeting held since 1999, adopted a final declaration reaffirming the participants’ “determination to take concrete steps towards early entry into force” and pledging “support for bilateral, regional, and multilateral outreach initiatives” to that end. The conference did not produce a work plan for such an effort.

In an effort to spur progress, the new executive secretary of the Preparatory Commission for the Comprehensive Test Ban Treaty Organization (CTBTO), Lassina Zerbo, announced the formation of 18-member Group of Eminent Persons to boost national and international efforts to bring the treaty into force. It includes several former foreign and defense ministers and senior diplomats, plus the co-chairs of the Sept. 27 conference, Hungarian Foreign Minister János Martonyi and Indonesian Foreign Minister Marty Natalegawa.

U.S. and Chinese officials reiterated their support for the treaty, but did not make any commitments on ratification. Mirroring comments made at the 2011 conference, Rose Gottemoeller, the acting U.S. undersecretary of state for arms control and international security, said that “there are no set time frames to bring the treaty to a vote, and we are going to be patient, but persistent in our outreach efforts.” Pang Sen, director-general of the Chinese Foreign Ministry’s Arms Control Department, pledged that his government would continue to “push forward the deliberation process” for Chinese ratification.

In August, following a visit by Zerbo to Beijing to meet with Foreign Minister Wang Yi, China agreed to transmit data from the CTBTO’s monitoring stations in China to the organization’s International Data Center (IDC) in Vienna. According to an Aug. 7 CTBTO press statement, “This is part of the testing and evaluation process that marks the first formal step towards certification of the monitoring stations in China.”

The International Monitoring System will consist of 337 monitoring facilities when complete. Around 85 percent have already been installed and are sending data to the IDC. To date, 10 of the 11 CTBTO monitoring stations hosted by China have been built.

More than 50 foreign ministers and senior government representatives met Sept. 27 at the United Nations to call for prompt action toward entry into force of the 1996 Comprehensive Test Ban Treaty (CTBT).

Civil Society Pushes Key States to Act on Nuclear Test Ban Treaty



For Immediate Release: Sept. 27, 2013

Media Contacts: Daryl G. Kimball, Director, Arms Control Association, (202-463-8270 ext. 107)

(New York/Washington) -- At a meeting of more than 100 senior government officials at the United Nations to discuss pathways to bring the 1996 Comprehensive Nuclear Test Ban Treaty into force, a diverse set of nongovernmental nuclear nonproliferation and disarmament leaders, as well as former government officials and diplomats are calling on all states to translate their words of support for the Treaty into concrete action.

In the statement to be delivered at the conference on behalf of civil society by Jonathan Granoff, president of the Global Security Institute, the nongovernmental experts said: 

"If both the letter and spirit of the CTBT are adhered to, then it will help curtail improvements in existing arsenals and lower the prestige of nuclear weapons programs. It strengthens the pursuit of international order based on the rule of law. However, the promise and benefits of the CTBT remain unfulfilled because the eight key states have failed to sign and/or ratify the treaty. It is time to act. Seventeen years have already passed by since the treaty was concluded. This is already the eighth Article XIV Conference on Facilitating CTBT Entry Into Force."

The civil society statement urged the conference to "help produce what previous conferences have not: a serious diplomatic action plan for getting the remaining holdout states on board."

The full text of the statement can be found here.

"Until the remaining eight Annex II outlier states finally ratify the treaty, entry into force will be delayed and the door to the renewal of nuclear testing will remain ajar," Granoff told the conference.

Eight more states including—China, the DPRK, Egypt, India, Israel, Iran, Pakistan, and the United States—must ratify before the CTBT can formally enter into force. To date, 183 states have signed the Treaty (including China and the United States) and 161 have ratified.


The Arms Control Association (ACA) is an independent membership organization dedicated to promoting public understanding and effective policies to address the threats posed by the world's most dangerous weapons: nuclear, biological, and chemical weapons, as well as certain types of conventional weapons that pose a threat to noncombatants. ACA publishes the monthly journal Arms Control Today.


(New York/Washington) -- At a meeting of more than 100 senior government officials at the United Nations to discuss pathways to bring the 1996 Comprehensive Nuclear Test Ban Treaty into force, a diverse set of nongovernmental nuclear nonproliferation and disarmament leaders, as well as former government officials and diplomats are calling on all states to translate their words of support for the Treaty into concrete action.

The Week Ahead, Sept. 21-28: Obama, Rouhani at the UN; Iran Meets IAEA; Syria Resolution

This bulletin highlights significant events in the world of arms control in the coming week, as compiled by staff and friends of the Arms Control Association. (Send your suggestions for events to be covered here .) - Jefferson Morley, Senior Editorial Consultant, Arms Control Today Obama, Rouhani to Speak at UN on Sept. 25 Iran's new president Hassan Rouhani has launched a charm offensive that opens new possibilities for the stalled talks relating to Iran's nuclear program. Those talks, between Iran and the United States and its P5+1 partners are expected to resume in October. Iran meets the...

Limited Test Ban Treaty Turns 50

Signing of the Partial Test Ban Treaty, 5 August 1963. Secretary of State Dean Rusk signing for the United States; Foreign Minister Andre Gromyko, signing for the Soviet Union; and Lord Hume signing for the United Kingdom. Photo: CTBTO. Note: The following essay by Daryl G. Kimball and Wade Boese was originally published in the October 2003 issue of Arms Control Today as " Limited Test Ban Treaty Turns 40" Like all first steps, it was long awaited, tentative, and not without risk. Yet, it also held out promise. The Limited Test Ban Treaty (LTBT) , the first agreement negotiated to regulate...

Obama Calls for Deeper Nuclear Cuts

Jefferson Morley and Daryl G. Kimball

President Barack Obama last month outlined a nuclear arms control agenda for his second term, calling for negotiated arms reductions with Russia, a fourth nuclear security summit, and a renewed push for treaties banning nuclear testing and the production of fissile materials.

In a June 19 address at the Brandenburg Gate in Berlin, Obama said, “We may no longer live in fear of global annihilation, but so long as nuclear weapons exist, we are not truly safe.” Obama’s initiatives build on the goals he announced in his April 2009 speech in Prague and on the 2010 New Strategic Arms Reduction Treaty (New START), which mandates reductions in U.S. and Russian nuclear arsensals by 2018.

While noting that New START would reduce deployed nuclear warheads “to their lowest levels since the 1950s,” Obama said, “[W]e have more work to do.”

“To move beyond Cold War nuclear postures,” Obama said he would seek to reduce the numbers of U.S. and Russian deployed strategic nuclear weapons by up to one-third. If implemented, the reductions would trim the two countries’ strategic nuclear arsenals from the limit of 1,550 deployed warheads mandated by New START to about 1,000 to 1,100.

Obama announced that the United States would host a nuclear security summit in 2016, aimed at protecting nuclear material around the world from theft or diversion by terrorist organizations or rogue states. It would be the fourth such gathering of Obama’s presidency. The third summit is scheduled to be held in the Netherlands next year. Until Obama’s announcement, it was unclear if the summits would continue beyond 2014.

The president pledged “to build support in the United States to ratify the Comprehensive Nuclear Test Ban Treaty,” echoing a promise he made in Prague four years ago. Obama also renewed his call for negotiations on a treaty that would end the production of fissile materials for nuclear weapons.

Obama did not provide any details about how he would promote the test ban treaty, which was rejected by the Senate in 1999. He also provided no specifics on advancing a fissile material treaty in the 65-nation Conference on Disarmament, which has been thwarted by objections from Pakistan.

Obama promised to work with NATO allies “to seek bold reductions in U.S. and Russian tactical weapons in Europe,” where the United States now maintains an estimated 180 nuclear warheads. The alliance’s 2012 Deterrence and Defence Posture Review document links changes in the alliance’s nuclear posture to Russia’s nuclear policy by stating that “NATO is prepared to consider further reducing its requirement for non-strategic nuclear weapons assigned to the Alliance in the context of reciprocal steps by Russia.” (See ACT, June 2012.)

The president announced that, after a “comprehensive review,” he approved new nuclear weapons employment guidance for the Defense Department that will lay the groundwork for the additional reductions, according to a June 19 White House summary.

The guidance directs the Pentagon to align U.S. military plans with the policies of Obama’s 2010 Nuclear Posture Review, which resulted in a report stating that the U.S. government will consider the use of nuclear weapons only in extreme circumstances to defend the vital interests of the United States or its allies and partners. Sources familiar with the review say that it was completed approximately 18 months ago.

The resulting strategy, says the summary, “will strengthen regional deterrence, and reassure U.S. allies and partners, while laying the groundwork for negotiations with Russia on how we can mutually and verifiably reduce our strategic and nonstrategic nuclear stockpiles.”

Administration sources say that senior U.S. and Russian officials soon will begin discussions on the options for further strategic nuclear reductions. “We are in close contact with our Russian counterparts and will be in the days and weeks and months ahead,” State Department spokeswoman Jen Psaki told reporters June 20.

In their public comments, senior Russian officials have responded coolly to Obama’s proposal. On June 23, Russian Foreign Minister Sergey Lavrov suggested that reductions beyond the levels in New START will make nuclear arsenals of the United States and Russia comparable to those of other countries with nuclear weapons.

“This means that further moves possibly proposed for reduction of actual strategic offensive arms will have to be reviewed in a multilateral format. And I’m talking not just official nuclear powers, but all countries that possess nuclear weapons,” Lavrov said on Rossiya 1 television. Russia has insisted that further offensive nuclear reductions also depend on a resolution of its concerns about U.S. strategic missile defense plans.

Obama’s speech was met with praise and criticism in the U.S. Senate. In a June 19 statement, Sen. Dianne Feinstein (D-Calif.), who chairs the intelligence committee, said that “the world will be better off without an unnecessarily high number of these powerful weapons. The Cold War is long gone and the United States and Russia must do more to adjust their deterrents to practicable standards.” Feinstein, along with 22 other Democratic senators, wrote to Obama earlier this year to encourage further action on nuclear reductions, the test ban treaty, and securing nuclear materials.

In a separate June 19 statement, Sen. Bob Corker (R-Tenn.), the ranking member of the Foreign Relations Committee, warned that additional limitations of the U.S. nuclear arsenal without modernization of existing forces could amount to “unilateral disarmament.” The same day, Corker and 23 other Republican senators wrote a letter to Obama insisting that “any further reductions in the U.S. nuclear arsenal should only be conducted through a treaty subject to the advice and consent of the Senate.”

Arms control advocates have said reciprocal, parallel reductions in strategic deployed nuclear forces can be implemented without a treaty and verified under the inspection procedures established by New START. A November 2012 report from the secretary of state’s International Security Advisory Board recommends a similar approach if the United States and Russia cannot agree on a new treaty. The report suggests the United States could accelerate its reductions under New START, allowing both sides to avoid “costly or destabilizing” programs to modernize strategic forces. (See ACT, November 2012.)

In his statement, Corker said Secretary of State John Kerry had assured him that any further reductions would occur in bilateral treaty negotiations subject to the advice and consent of the Senate. But a State Department spokesman denied that, saying Kerry had only agreed that the Senate would be “consulted.”

“At this point, it’s premature to speculate on precisely what such agreement…might encompass or how it would be established,” the spokesman said.

The U.S. president laid out his arms control agenda, prompting a cool reply from Russia and a partisan reaction from Capitol Hill.

Nuclear Nonproliferation Treaty at 45

President Lyndon Johnson looking on as Secretary of State Dean Rusk prepares to sign the NPT, 1 July 1968.(Source: Lyndon B. Johnson Presidential Library.) By Daryl G. Kimball Forty-five years ago today, the United States, the Soviet Union, the United Kingdom, and dozens of other countries signed the nuclear Nonproliferation Treaty (NPT) at ceremonies in Washington, Moscow, and London. In his remarks at the July 1, 1968 signing ceremony , U.S. President Lyndon Johnson called it "... a very reassuring and hopeful moment in the relations among nations. We hope and expect that virtually all the...

Obama's Nuclear Challenge

Daryl G. Kimball

In his June 19 address in Berlin, President Barack Obama sought to jump-start progress on his second-term nuclear risk reduction agenda. The president declared,”[S]o long as nuclear weapons exist, we are not truly safe. Peace with justice means pursuing the security of a world without nuclear weapons, no matter how distant that dream may be. Complacency is not in the character of great nations.”

Doing nothing in the face of grave nuclear weapons threats is not an option. Obama’s renewed call to action for further nuclear cuts and U.S. ratification of the Comprehensive Test Ban Treaty (CTBT) is welcome and overdue.

Obama’s centerpiece announcement was that he had completed a review of nuclear weapons employment guidance and determined that the United States can reduce the number of strategic nuclear weapons it deploys by up to one-third—from 1,550 under the New Strategic Arms Reduction Treaty (New START) to between 1,000 and 1,100—and would seek reciprocal Russian reductions through negotiations.

Unfortunately, the scope of Obama’s nuclear disarmament proposals is too modest and the pace of action too slow. The cuts outlined by the president are a good start, but a level of 1,000 to 1,100 is only 200 to 300 warheads below the number to which the United States was prepared to agree during the negotiations on New START four years ago if Russia had not insisted on setting a ceiling of 1,550 through the year 2021.

In the 21st century, 1,000 deployed strategic warheads provide more than enough nuclear firepower to deter any current or potential nuclear adversary. In April 2012, former Sen. Chuck Hagel (R-Neb.), who now is secretary of defense, endorsed a study recommending the United States move toward a nuclear force of 450 deployed strategic weapons by 2022.

In the weeks ahead, the president must follow up on his Berlin speech by making a stronger case for why much deeper strategic nuclear reductions improve U.S., Russian, and global security.

Although a healthy majority of the American public and most U.S. senators support further reductions of nuclear weapons deemed in excess of deterrence requirements, some senators oppose reductions of any kind, while others insist that any further nuclear cuts should be made only through a new, formal agreement subject to Senate approval.

Congress surely needs to be consulted, but it should not put unnecessary roadblocks in the way of a more cost-effective and appropriately sized nuclear force. The Joints Chiefs of Staff, the Pentagon, and the White House already have determined that at least one-third of the current deployed strategic nuclear force is superfluous to U.S. nuclear military requirements.

Republican senators need to recognize that, by insisting on new treaty negotiations, they could give Russian President Vladimir Putin a veto over cuts of unnecessary and expensive U.S. strategic nuclear weapons. Even after the cancellation in March of U.S. plans for more-sophisticated missile interceptors in Europe, Moscow is reluctant to begin formal treaty talks. If talks do begin, they will be more complex and time consuming than New START.

U.S. and Russian leaders need not wait for a follow-on treaty. As they explore options for a new treaty, Obama and Putin should announce parallel, reciprocal reductions to 1,000 or fewer strategic deployed warheads within the next five years, to be verified using the monitoring provisions established by New START.

This strategy would help compel Russia to build down rather than build up its strategic nuclear forces. Russia, whose nuclear force already is below the New START limits, is developing a new, heavy intercontinental ballistic missile to match U.S. force levels. More-rapid reductions of U.S. and Russian nuclear forces, which comprise 95 percent of global stockpiles, also would increase pressure on China and other nuclear-armed states to join the nuclear disarmament enterprise, an objective that leaders in Russia and United States say they support.

By scaling back its nuclear force to 1,000 deployed strategic warheads, the United States can trim $39 billion from the Defense Department’s costly plan for new strategic submarines, missiles, and bombers over the next decade, according to a 2013 Arms Control Association analysis.

In Berlin, Obama pledged to “work with our NATO allies to seek bold reductions in U.S. and Russian tactical weapons in Europe.” Unfortunately, NATO has been unable to reach agreement on new proposals for tactical nuclear arms control. For its part, Russia says it will not consider limits on its far larger stockpile of tactical nuclear weapons until all such U.S. weapons are withdrawn from Europe.

More than 20 years after the end of the Cold War, there is no military rationale for Russia’s arsenal of 2,000 tactical nuclear warheads, nor is there any military requirement for the 180 U.S. nuclear bombs in Europe. Bolder action is required to break the impasse. Obama should call Russia’s bluff and announce he is prepared to withdraw the remaining U.S. tactical bombs within five years and put pressure on Russia to take reciprocal action.

To overcome the challenges standing in the way of a world free of nuclear weapons, Obama and his team will need to devote greater energy, creativity, and determination to the cause.

In his June 19 address in Berlin, President Barack Obama sought to jump-start progress on his second-term nuclear risk reduction agenda. The president declared,”[S]o long as nuclear weapons exist, we are not truly safe. Peace with justice means pursuing the security of a world without nuclear weapons, no matter how distant that dream may be. Complacency is not in the character of great nations.”


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