Jeffrey Lewis and Herbert Lin join the Bulletin’s Science and Security Board

The Bulletin is honored to welcome Jeffrey Lewis and Herbert Lin to its Science and Security Board (SASB).

The SASB is a select group of globally recognized leaders with a specific focus on nuclear risk, climate change, and disruptive technologies. The SASB provides the Bulletin with objective external perspectives on trends and issues in these fields and connects the organization to outside experts. It also is responsible for setting the time on the Doomsday Clock each year.

Lewis joins the Board as a Distinguished Scholar of Global Security at Middlebury College and Distinguished Fellow at the Foreign Policy Research Institute. He is also a member of the National Academies of Sciences, Engineering, and Medicine’s Committee on International Security and Arms Control, which conducts dialogues with counterparts in China, Russia, and India. He also serves on the Frontier Red Team at Anthropic, an artificial intelligence company.

From 2022 to 2025, Lewis was a member of the U.S. Secretary of State’s International Security Advisory Board.

He is the author of two scholarly books, The Minimum Means of Reprisal: China’s Search for Security in the Nuclear Age (MIT Press, 2007) and Paper Tigers: China’s Nuclear Posture (International Institute of Strategic Studies, 2014), as well as a novel of speculative fiction, The 2020 Commission on the North Korean Nuclear Attacks Against the United States (Mariner, 2018).

“I am absolutely thrilled to welcome Jeffrey Lewis as the newest member of the Science and Security Board,” said Bulletin President and CEO Alexandra Bell. “With Jeffrey, we are gaining someone with an extensive background on nuclear risks in Asia and unparalleled skills in open-source intelligence analysis. Jeffrey is also an accomplished science communicator. His ability to deftly outline existential threats and the potential methods for reducing those threats is unmatched. He will bring energy, candor, and a wry sense of humor to the SASB.”

Previously, Lewis was the director of the Nuclear Strategy and Nonproliferation Initiative at the New America Foundation and executive director of the Managing the Atom Project at the Belfer Center for Science and International Affairs at Harvard University. He also worked in the Office of the Undersecretary of Defense for Policy and at the Center for Strategic and International Studies.

“Martyl Langsdorf’s Clock is among the most powerful works of graphic art of the last century, conveying the immediacy of nuclear danger then and now,” said Lewis. “Serving on the Science and Security Board is both an honor measured by its company—from the first board in 1945 to those who sit on it today—and a responsibility to inform the public, plainly and honestly, about the dangers we face.”

Lin previously served on the SASB from 2016 to 2025, and he is currently a senior research scholar and research fellow at Stanford University.

“Herb Lin is an existential risk polymath, and we are so grateful to have him back on the Board,” said Bulletin President and CEO Alexandra Bell. “His knowledge of nuclear risks, as well as disruptive technologies, including AI, is even more important as the challenges in these sectors continue to intertwine. From considering how AI impacts nuclear escalation to outlining how he makes the threat of nuclear war personal for his students, Herb continues to provide invaluable perspective and creative solutions to some of the most complex and consequential threats humanity faces.”

Lin’s research interests relate to the intersection of emerging technologies and national security, especially the digital technologies of cyber war, information operations, and artificial intelligence. In 2016, he served on President Obama’s Commission on Enhancing National Cybersecurity. He has also served as a professional staff member and staff scientist for the House Armed Services Committee (1986-1990), in which his portfolio included defense policy and arms control issues.

“I’ve been a follower of the Bulletin for half a century, and I’ve been able to see the Bulletin’s influence time and time again,” said Lin. “And there’s more to come. From the millions reached by the Doomsday Clock announcement each year to the rising experts the Bulletin uplifts in its Voice of Tomorrow column, I am grateful to be able to help shape the path of an organization that is continuously engaging the public on existential threats in unique and unexpected ways and helping to find off-ramps to a better future for us all.”

Learn more about the Science and Security Board.