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Hans M. Kristensen

Director, Nuclear Information Project, Federation of American Scientists

Born in: Denmark
Hans M. Kristensen

Hans M. Kristensen has dedicated his life to nuclear disarmament and nonproliferation, and to holding governments accountable when it comes to nuclear issues. After finishing gymnasium (Denmark’s equivalent of high school), Kristensen joined Greenpeace Denmark to work on the environmental organization’s nuclear disarmament campaign. This was the beginning of a more than decade-long career with Greenpeace Denmark and Greenpeace International, where he coordinated the Nuclear Free Seas Campaign in Denmark, Norway, Finland, and Sweden. In 1991, Kristensen came to the United States to work as the senior researcher for Greenpeace International’s Military Information Unit. After returning to Denmark in 1997 to serve as a special advisor to the Danish Ministry of Defense, he came back to the U.S. to direct the Nuclear Strategy Project at the Nautilus Institute, a Berkeley-based public policy think tank hosting an online repository of Freedom of Information Act (FOIA) documents that give the public direct access to declassified information about nuclear planning and operations.

Kristensen is currently the director of the Nuclear Information Project at the D.C.-based Federation of American Scientists, a leading arms control organization founded by the Manhattan Project physicists who built the first atomic bombs. His work focuses on the role of nuclear weapons in the post-Cold War era, and he specializes in using Freedom of Information Act requests to monitor the status of the U.S. nuclear arsenal. In 2005, Kristensen’s research led to the disclosure that preemptive nuclear strikes were being incorporated into the U.S. post-Cold War Joint Nuclear Doctrine for the first time. His findings made headlines around the world, prompting the Senate Armed Services Committee to request briefings from the Pentagon, and ultimately led to the Pentagon cancelling the revised Joint Nuclear Doctrine document.

Kristensen coauthors the “FAS Nuclear Notebook” column in the Bulletin of the Atomic Scientists and the “World Nuclear Forces” overview in the SIPRI Yearbook, the go-to resource for tracking the status of the world’s nuclear arsenals, a publication of the Stockholm International Peace Research Institute. In addition to his research publications and media interviews, Kristensen tweets about nuclear weapons and non-nuclear issues, such as his 2019 U.S. naturalization ceremony: “I’m excited and honored to share the privileges, opportunities, and responsibilities of this great nation.”

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