Happy to contribute a 200-word take to this @carnegieeurope.bsky.social panel on France's nuclear strategy of "forward deterrence." Feat. @mgmessmer.bsky.social, @paulvanhooft.bsky.social, @drfranksauer.bsky.social, @hfayet.bsky.social, @laurensukin.bsky.social, @nuclear-jim.bsky.social, & more.

Taking the Pulse: Is France’s New Nuclear Doctrine Ambitious Enough?

French President Emmanuel Macron has unveiled his country’s new nuclear doctrine. Are the changes he has made enough to reassure France’s European partners in the current geopolitical context?

carnegieendowment.org

I'm thrilled to have a contract with @academic.oup.com for my book on "Entanglement and Unintended Escalation." (There'll be a better title!) The manuscript is drafted and currently being revised. Hopefully should be out second half of next year!

Testing nuclear weapons by detonating warheads is like “nuking yourself in the foot,” writes @nuclear-jim.bsky.social. Trump can stop nuclear anarchy by testing in ways that don’t spark a global arms race or give away the U.S.’s data advantage. More here: carnegieendowment.org/emissary/202...

Trump Has an Out on Nuclear Testing. He Should Take It.

Sometimes good policy can be as simple as not nuking yourself in the foot.

carnegieendowment.org

Let's not nuke ourselves in the foot! I explain why it's so difficult to know if China and Russia are conducting ultra-low yield tests and why, even if they are, it's not in U.S. interests to restart testing. @carnegieendowment.org @carnegienpp.bsky.social carnegieendowment.org/emissary/202...

Trump Has an Out on Nuclear Testing. He Should Take It.

Sometimes good policy can be as simple as not nuking yourself in the foot.

carnegieendowment.org

I am entirely indifferent whether, in the event of a nuclear war, I am incinerated by a nuclear warhead delivered by a "traditional" ICBM, a hypersonic glider, a nuclear-powered cruise missile, or a nuclear-powered torpedo. All seem equally suboptimal to me.

elmo from sesame street standing in front of a wall

ALT: elmo from sesame street standing in front of a wall

media.tenor.com

¯\_(ツ)_/¯

The End of MAD? Join me, Steve Fetter, @jaysankarans.bsky.social, TD MacDonald, Ton Stefanik, @lauraegrego.bsky.social, @fiona-cunningham.bsky.social, and Charlie Glaser to discuss whether technological developments are undermining mutually assured destruction. Link for virtual rego in next post.

a man in a shirt and tie is screaming with his hands in the air .

ALT: a man in a shirt and tie is screaming with his hands in the air .

media.tenor.com

What exactly is the government hiding in Tucson? Not much, says @nuclear-jim.bsky.social. He got an interesting souvenir there, regardless. See the first installment of Carnegie Office Hours for more treasures from James (if not nuclear secrets) here: buff.ly/dlUzF6n

I feel pretty strongly the @nytimes.com has the wrong framing here. This isn't serious; it's pathetic. I'd suggest something like: "Trump throws social media hissy fit invoking nukes after public spat with ex-president of Russia."

As much as I deplore nuclear signaling by tweet--can't believe I just wrote that--I would NOT necessarily assume there's a been change to the US nuclear posture. The U.S. always keeps ~4/5 SSBNs at sea ready to fire.

James Acton@nuclear-jim.bsky.social · last yr.

Ahem (Deleted earlier version, which was missing caption!)

Ahem (Deleted earlier version, which was missing caption!)

Ah, yes, that crucial ninth significant figure...

Good gracious, Ignatius! Why I disagree with the normally excellent David Ignatius; recent oped on Iran.

James Acton@nuclear-jim.bsky.social · last yr.

Ignatius's oped is written as if it's a news story. The "news" in this case is that--SURPRISE!--an Israeli source backed up claims by the Israeli government! (3/n) x.com/james_acton3...

The case for attacking Iran relied on emphasizing its technical prowess. The case that strikes were successful requires claiming that Iran is technically incompetent. foreignpolicy.com/2025/07/25/i...

There’s More Than One Way to Build a Bomb

Iran doesn’t need to rebuild its damaged facilities to sprint for a nuclear weapon.

foreignpolicy.com

On Friday, I argued in @foreignpolicy.com that Trump admin claims it had set Iran back by "years" were true but disingenuous. The same day, the normally excellent David Ignatius amplified the misleading U.S. and Israeli narrative. www.washingtonpost.com/opinions/202... Let's take a look... (1/n)

Opinion | The 12 days that turned back the clock on Iran’s nuclear program

Israeli and American assessments agree Tehran’s infrastructure to finish a bomb is shattered.

washingtonpost.com

🎶When you attend a funeral, It is sad to think that sooner orl… …ater, those you love will do the same for you. And you may have found it tragic, Not to mention other adjec.. …tives to think of all the weeping they will do. 🎶 RIP, Mr Lehrer.

Al Yankovic@alyankovic.bsky.social · last yr.

My last living musical hero is still my hero but unfortunately no longer living. RIP to the great, great Mr. Tom Lehrer.

Me in @foreignpolicy.com. The Trump administration's claim that Iran would need "years" to rebuild its previous nuclear program is like asserting that an unlocked bank vault would be impervious to a cyberattack. It’s true but misses the point. foreignpolicy.com/2025/07/25/i...

There’s More Than One Way to Build a Bomb

Iran doesn’t need to rebuild its damaged facilities to sprint for a nuclear weapon.

foreignpolicy.com

had @nuclear-jim.bsky.social on Angry Planet to explain what the current nuclear arm's race looks like. It's bad! He's got a solution that sounds radical, but is more palatable than living in a world where everyone is spending billions to construct more nukes

How Many Nukes Does It Take to Win a War? (Trick Question)

The world is living with a Cold War hangover.

angryplanetpod.com

🧵How much damage was done to Iran's nuclear program? An analysis of Friday's reporting of the U.S. government assessment. I'll focus on the @nytimes.com, which was clearer than the earlier but confused @nbcnews.com story. (1/n) www.nytimes.com/2025/07/17/u...

New Assessment Finds Site at Focus of U.S. Strikes in Iran Badly Damaged

nytimes.com

I can think of no reason at all why Iranian leaders won’t jump at the chance to follow the “Libya model.” Can you, Muammar?

Important piece from @nuclear-jim.bsky.social about how to develop a better nuclear deterrence posture. www.cfr.org/report/optim... James’ deep thinking on these matters is desperately needed at a time when deterrence debate at times sounds more like Cold War grab-bag posturing on autopilot.

Optimal Deterrence

The United States faces growing dangers of nuclear escalation, a new arms race, and proliferation. This report recommends an improved strategy for “optimal deterrence” and a path to rebuilding relati…

cfr.org

Personally, I'm open to all three possibilities--that all, some, or none of the HEU was moved pre-war. I simply don't know and there appears to be real disagreement among intel agencies here.

Seven Yakima@sevenyakima.bsky.social · last yr.

Is the assessment that the HEU has not been removed before the strikes now the commonly accepted view? And if so, isn't it better if the HEU is maybe not completely buried than if it had been moved to unknown sites? www.timesofisrael.com/senior-israe...

It'd be a pretty catastrophic outcome *IF* the attacks on Fordow failed to destroy centrifuges and they can be put back into service. I'm not claiming this is the case, but U.S. officials seem to be hinting it's a possibility. (1/n) @hugolowell.bsky.social

lol

Matej Rafael Risko@matejrisko.bsky.social · last yr.

And you just lost the nuclear war, using Colin Gray’s terminology, the enemy will have enough (~50y) time to recover, you will never fully recover o the pre-war period. CMI is dangerous nonsense. 5/5

🧵Introducing optimal deterrence. Here's my proposed U.S. nuclear strategy for managing escalation, arms racing, and proliferation with two nuclear peers, published through @cfr.org. Health warning: If you like counterforce, take a DEEP breath before reading on. (1/n) www.cfr.org/report/optim...

Optimal Deterrence

The United States faces growing dangers of nuclear escalation, a new arms race, and proliferation. This report recommends an improved strategy for “optimal deterrence” and a path to rebuilding relati…

cfr.org

My friend, Joshua Pollack, penned this beautiful and wry double obituary of his father, Jonathan Pollack, and his first boss, Barry Blechman. www.armscontrolwonk.com/archive/1220...

This.

James Acton@nuclear-jim.bsky.social · last yr.

The administration has argued that the destruction of Iran's uranium metal production lines at Isfahan will set its nuclear-weapon program back by "years." At Arms Control Wonk, I argue it may not even set Tehran back by months. www.armscontrolwonk.com/archive/1220...

The administration has argued that the destruction of Iran's uranium metal production lines at Isfahan will set its nuclear-weapon program back by "years." At Arms Control Wonk, I argue it may not even set Tehran back by months. www.armscontrolwonk.com/archive/1220...

In today's @financialtimes.com, I reflect on the implications of the joint Israeli-US attacks on Iran for a fragile and bruised nonproliferation regime on.ft.com/45Jehd3

Iran attack could be the death knell for nuclear non-proliferation

More countries will seek atomic weapons unless Europe and its allies defend a flawed but vital treaty

on.ft.com