Director, Project on Nuclear Issues & Sr Fellow, Defense and Security Department CSIS @csisponi. Associate @warstudies @rusi_org @MIT_CNSP Bluesky: heatherwilly
Boston (and Washington, DC)
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Imagine a world without nuclear weapons. It may be closer than we think, and it may not be the world disarmament advocates have in mind. My new piece in @TWQgw twq.elliott.gwu.edu/ (free access through TWQ website for the next few months) 1/
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Heather Williams retweeted
CISAC is hiring! Professor Scott Sagan is seeking a tenacious research assistant with first-rate analytical capabilities and outstanding academic credentials to assist on research, support teaching, and work on a variety of projects.
Apply here⤵️
fa-exuf-saasfaprod1.fa.ocs.o…
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Heather Williams retweeted
I did some digging into concerning delays by Washington in funding critical WMD verification agencies—the Organization for the Prohibition of Chemical Weapons @OPCW and International Atomic Energy Agency @iaeaorg.
Congress should request more information from @SecRubio and @michaelgwaltz. fdd.org/analysis/washington-…
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Heather Williams retweeted
We're hiring @JamesMartinCNS for 2027-2028 academic year! Postdoc/Predoc fellowship on AI & nuclear/biological security. Policy & technical backgrounds welcome.
Location: Monterey, CA
Salary: $67.9K–$100K
Priority deadline: Feb. 1, 2027
Apply or share! apply.workable.com/middlebur…
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As of October 15, 2026, a Russian satellite called Cosmos 2612 is moving into position for close-proximity operations with a U.S.-registered commercial satellite supporting Ukraine. “No one should assume to know what Russia will do next, but the potential for a threat is there,” write @crswope and Chantal Li.
Read: csis.org/analysis/could-russ…
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Heather Williams retweeted
This month, PONI's @heatherwilly and Diya Ashtakala were published in The Washington Quarterly!
In "Disarmament by Replacement: Imagining Alternatives to Nuclear Weapons," Williams argues that current visions for disarmament are focused on the wrong challenge: the more fundamental issue is not the slowing pace of disarmament, but rather the failure of the nuclear order to account for the impact of emerging technologies on disarmament.
In "India-Pakistan Nuclear Signaling and China’s Trilemma," Ashtakala argues that the next India-Pakistan confrontation will likely involve China at the outset, increasing escalation risk and requiring urgent revitalization of confidence-building measures among them.
Read both analyses here: twq.elliott.gwu.edu/
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Heather Williams retweeted
Thread. This is very much now Europe's war, as the US has left the stage. Europe will need to take lots of urgent action to aid Ukraine throughout this winter. Need to start now.
I haven’t seen the plan described in this article (although I want to) but I feel confident about its content and what’s next. Russian strategy has discussed for 10+ years what we are seeing now as strikes. A 🧵 on the calculated cruelty in the strategy:
nytimes.com/2026/10/02/world…
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Heather Williams retweeted
Come work with me and the other good folks at the Kissinger Center! New opportunities for pre and post doctoral fellowships now open for next academic year.
@AWConsortium @KissingerCenter
awconsortium.org/opportuniti…
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Heather Williams retweeted
Applications for the 2027 Nuclear Scholars Initiative are now live!
The Nuclear Scholars Initiative aims to provide top graduate students and young professionals from around the country with a unique venue to interact and dialogue with senior experts on nuclear weapons issues. Those accepted into the program are hosted once per month over the course of six months at CSIS in Washington, DC where they participate in two-day workshops.
Applications are due Monday, November 2 at 11:59 PM ET. Please view all application requirements here: nuclearnetwork.csis.org/prog…
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Heather Williams retweeted
Le Centre for Global Security and Governance (@CGSG_SciencesPo) lance un appel à contributions pour son colloque « Des communs sous les armes? L’extension du domaine de la guerre », qui se tiendra le 16 mars 2027. Propositions avant le 30 octobre!
Appel à contributions: « Des communs sous les armes ? L’extension du domaine de la guerre », colloque organisé par le Centre for Global Security and Governance de Sciences Po le 16 mars 2027. Date limite: 30 octobre 2026.
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Imagine a world without nuclear weapons. It may be closer than we think, and it may not be the world disarmament advocates have in mind. My new piece in @TWQgw twq.elliott.gwu.edu/ (free access through TWQ website for the next few months) 1/
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So what could replace nuclear weapons' deterrence, prestige, and hard-target roles? Three candidates: advanced conventional weapons, synthetic biological agents, or something a "helpful" AI comes up with that no human anticipated. 4/
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A world without nuclear weapons could be one with weapons that are more usable, less humane, and less under human control. The nuclear order can't keep operating in a silo. What needs to happen: a P5 workshop on AI and nuclear weapons, a Track 1.5 initiative with tech companies, and bringing in next-gen experts. /end
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Heather Williams retweeted
He got it from his mama.
Bear 89, aka Backpack, is the 2026 Fat Bear Week champ. Turns out hefty runs in the family.
His mom, Holly the Duchess of Density, won in 2019. She carried him on her back as a cub and helped him survive a serious leg injury. Now her little Backpack has a crown of his own. 👑
ALT An offensively large brown bear with massive girth and several fat rolls.
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You should read this by Rebecca Gibbons on the limits of the AI-nuclear analogy
AI is often compared to nuclear weapons. Does the analogy help us understand AI, or is it pushing policy in the wrong direction? warontherocks.com/2026/09/th…
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Heather Williams retweeted
@hippocrise seems to think that they can compete with #fatbearweek .
Stay in your lane you furless water cow…..
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Heather Williams retweeted
Perspective:
Before and after
#fatbearweek
Respect the process 😂
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#fatbearweek is the best thing on social media right now
Nothing says" I've got my life together" like 1,000 lbs of salmon-fueled confidence.
ALT Large brown bear standing on shoreline.
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My colleague Jane Nakano and I weigh-up the opportunities and challenges of the Saudi 123 agreement: on the one hand, it's an opportunity to compete with China for regional influence. On the other hand, depending on the details, it could come with 3 risks to the nuclear regime. @csisponi @CSISDefense @CSISEnergy
NEW COMMENTARY:
PONI's Heather Williams and Energy Security and Climate Change's Jane Nakano analyze the Saudi 123 Agreement, arguing the proposed U.S.-Saudi civil nuclear agreement has both risks and opportunities for U.S. national security. What would Washington gain? How might it affect global nonproliferation norms, or shape global interests in nuclear defense capacity? How might it impact U.S. competition with China?
To explore these questions in greater depth, read the full commentary here: csis.org/analysis/nuclear-st…
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