Digests and Blog

 ACA Executive Director Daryl Kimball provides an expert commentary on the now unconstrained strategic nuclear arsenals of the United States and Russia in the Bulletin of the Atomic Scientists.The expiration of the New Strategic Arms Reduction Treaty (New START) this week means that the United States and Russia are now unconstrained and could soon begin increasing their strategic deployed arsenal by uploading additional warheads on existing missiles and bombers—for the first time in more than 35 years. The end of New START could also open a new phase of dangerous nuclear competition—one that…

Countryman's remarks begin at timestamp 27:25.Thomas Countryman on New START Expiry and the Value of Arms ControlFebruary 4, 2026Prior to New START’s expiration, ACA board chair Tom Countryman joined Massachusetts Senator Ed Markey, Oregon Senator Jeff Merkley, California Representative John Garamendi, ACA Executive Director Daryl G. Kimball, FAS Director of Global Risk Jon Wolfsthal, and Senior Fellow at the Center for European Policy Analysis Lynn Rusten to urge the replacement of New START and a return to negotiations to prevent an new and more dangerous three-way arms race."I want to…

With the risks of new nuclear-armed States on the rise, the nuclear non-profileration regime is in danger of collapse. In 2026, Iran will continue to dominate the headlines as the most likely country to exit the Non-Proliferation Treaty (NPT) or develop nuclear weapons in violation of its treaty obligations. Beyond Tehran, however, additional countries are likely to move closer to weaponization as debates about the security value of nuclear deterrence intensify and technical barriers to proliferation erode.For decades, since the NPT entered into force in 1970, international efforts to prevent…

With signals pointing to a resumption of U.S.-Iran talks, the Trump administration has another opportunity to reduce Tehran’s proliferation risk and the likelihood of the United States getting sucked into further, counterproductive military strikes against Iran’s nuclear program. The U.S. and Israeli attacks on Iran’s nuclear facilities in June—despite no evidence of a decision to weaponize—did destroy key Iranian nuclear facilities. But Iran’s capability to build a bomb, and its stockpile of uranium enriched to near weapons-grade levels, remains intact and unmonitored, increasing the risk of…

 Last autumn, Greg Thielmann stepped down from the board of directors of the Arms Control Association (ACA) after nearly a decade of counsel and support. This was Thielmann’s fourth retirement, after careers as a foreign service officer with the U.S. Department of State, as a Congressional staff member, and as a member of the staff at ACA, where he served as senior fellow from 2010-2016.Thielmann attained a public profile in 2003 following the U.S. invasion of Iraq, when he accused the Bush administration of misconstruing intelligence assessments to justify the war. Thielmann had served in…

Inside ACA December 2025There is no doubt that 2025 has been a brutally difficult year for international peace and security.Nuclear dangers are on the rise. Nuclear weapons spending is way up. Key nuclear norms, and agreements designed to reduce nuclear dangers are in jeopardy. Leading states have failed to engage in commonsense arms control diplomacy. For the sake of future generations (and ours) we cannot allow the situation to deteriorate further in 2026.You can count on ACA to continue to be on the front lines on some of the most important decisions and debates in 2026 – decisions that…

Nuclear Disarmament MonitorDecember 11, 2025In a new white paper on arms control, disarmament, and nonproliferation released Nov. 27, China’s Ministry of Foreign Affairs reaffirmed its long-standing policy of no-first-use of nuclear weapons and a nuclear strategy of self-defense, while providing an only limited glimpse into the nuclear power’s rationale for an ongoing large-scale strategic build-up. The document, which has been anticipated by Chinese experts for more than a year, is the most definitive statement of Chinese policy on nuclear weapons in some 20 years. In the intervening decades…

The increasing availability of benchtop nucleic synthesis equipment paired with the rapid evolution of artificial intelligence (AI) capabilities raises concerns that malicious actors could clandestinely synthesize dangerous pathogens or toxins with biological-weapon potential. Current national and international regulatory mechanisms do not adequately address the rising biosecurity risks that accompany this development.Instead of strengthening oversight, a May 5 White House Executive Order has created uncertainty over the status of a previously established framework on nucleic acid synthesis…

Inside the Arms Control AssociationOctober 2025At this pivotal and difficult juncture in the history of the nuclear age, ACA has been focused on preventing the guardrails against nuclear catastrophe from breaking down, and preparing to seize the breakthrough moment when we can advance again in the direction of a world free of nuclear weapons.One key guardrail that is going away is the 2010 New Strategic Arms Reduction Treaty (New START), which will expire in some 100 days. In 2021 ACA successfully lobbied the Biden administration to extend New START for five years. The treaty cannot be…

Nuclear Disarmament MonitorOctober 17, 2025The 80th session of the UN General Assembly First Committee on disarmament and international security is underway. UN member states are gathering from Oct. 8 to Nov. 7 in New York to discuss and adopt resolutions and decisions to renew their commitments to advancing disarmament and maintaining international peace and security.Coloring many conversations is the fast-approaching expiration of the New Strategic Arms Reduction Treaty (New START) on Feb. 5, 2026. As the First Committee convenes, a Russian proposal to continue adhering to the treaty’s…