Jeffrey Lewis

Jeffrey Lewis

Creator
0 followers

NTI/MIIS scholar; nuclear deterrence, arms control, missile forces (OSINT).

Trump's Promised Superior NK Deal Never Materialized
SocialFeb 26, 2026

Trump's Promised Superior NK Deal Never Materialized

The Trump people promised a better deal with North Korea than either the 1994 Agreed Framework or the JCPOA with Iran. That didn't happen then and it won't happen now. They might get some sort of deal, but it...

By Jeffrey Lewis
Questioning Trump's Grasp on Iran's Missile vs Nuclear Sites
SocialFeb 26, 2026

Questioning Trump's Grasp on Iran's Missile vs Nuclear Sites

I wonder if Trump is capable of distinguishing Iran's missile facilities (definitely reconstituting) from its nuclear facilities (much less clear), or whether its all mixed together in his head.

By Jeffrey Lewis
Witkoff Warns 60% Enrichment Risks Rapid Further Enrichment
SocialFeb 26, 2026

Witkoff Warns 60% Enrichment Risks Rapid Further Enrichment

Again, I think that's clearly not what Witkoff meant -- although I accept his statement was exceptionally maladroit. IMHO Witkoff was explaining, conceptually, why the retention of the 60% enrichment would be a problem under a deal (ie it...

By Jeffrey Lewis
Witkoff Warned 60% Enrichment Poses Proliferation Risk
SocialFeb 26, 2026

Witkoff Warned 60% Enrichment Poses Proliferation Risk

This distorts what Witkoff said. He was abstractly explaining why 60% enriched uranium posed a proliferation risk.

By Jeffrey Lewis
Iran Could Field ICBM‑class Missile Within 2‑3 Years
SocialFeb 25, 2026

Iran Could Field ICBM‑class Missile Within 2‑3 Years

We estimated the Zoljanah would have a 4,000-5,000 km range as a missile so yeah ... US and Soviet experience would suggest they are 2-3 years from an ICBM-class system following a decision to go for it.

By Jeffrey Lewis
Iran May Field 60 ICBMs by 2035, Not Just SLVs
SocialFeb 25, 2026

Iran May Field 60 ICBMs by 2035, Not Just SLVs

There is a widespread misunderstanding about the @DefenseIntel claim that Iran could develop an ICBM on the basis of SLVs by 2035. The same document also says that by 2035, it could have 60 (SIX-OH) ICBMs. https://t.co/cEpVUZ7I5Y

By Jeffrey Lewis
North Korea, Iran Co‑Develop LPRE, Potential ICBM Threat
SocialFeb 25, 2026

North Korea, Iran Co‑Develop LPRE, Potential ICBM Threat

North Korea's "3.18 Revolution" liquid propellant rocket engine (LPRE) was co-developed with Iran. Iran released pictures of an itty bitty model of one at the space day last year. Might be for an SLV, but also makes a great ICBM...

By Jeffrey Lewis
China’s Indifference to US Pressure Still Raises Global Concerns
SocialFeb 24, 2026

China’s Indifference to US Pressure Still Raises Global Concerns

+1. Even if China doesn't care about US pressure, talking to the CD raises questions among countries that China does care about.

By Jeffrey Lewis
Lop Nor Event Dwarfed by Comparison Earthquakes, Data Shows
SocialFeb 24, 2026

Lop Nor Event Dwarfed by Comparison Earthquakes, Data Shows

We now have a slide from @UnderSecT on the suspicious event at Lop Nor in China. One can see how much smaller this event is than the earthquakes selected for comparison by looking at the noise prior to the start...

By Jeffrey Lewis
Unprecedented Action: CD's Most Active Period in Decades
SocialFeb 24, 2026

Unprecedented Action: CD's Most Active Period in Decades

Say what you will, but this is more action than the CD has seen in decades.

By Jeffrey Lewis
Dark Eagle Launchers Get Quirky Censored Names, Sparking Humor
SocialFeb 23, 2026

Dark Eagle Launchers Get Quirky Censored Names, Sparking Humor

One thing thing about DARK EAGLE is that each launcher has a name -- Hyperion, Iron Giant, Shockwave, etc. -- but censors sometimes blur them. I like to imagine its not OPSEC at all, but just adult supervision, ie the...

By Jeffrey Lewis
Witkoff's Enrichment Claim Misunderstood, Not a Bomb Threat
SocialFeb 22, 2026

Witkoff's Enrichment Claim Misunderstood, Not a Bomb Threat

The criticism of Witkoff is unfair. He arguing, admittedly not all that adroitly, that enrichment levels of 60% exceed what's necessary for most civilian purposes and could be quickly ("probably a week") enriched further to produce "bomb-grade material." https://t.co/Zw26IV2hBJ

By Jeffrey Lewis
Nuclear Deterrence Alone Can't Stop Aggression without Conventional Strength
SocialFeb 20, 2026

Nuclear Deterrence Alone Can't Stop Aggression without Conventional Strength

This, by the way, is why I am skeptical that Ukrainian nuclear weapons would have deterred Putin. He thought Ukraine would collapse, not resist. Deterrence usually works, but it is not foolproof and it does not replace a credible conventional...

By Jeffrey Lewis
Single Station Detection Yields Uncertain Location
SocialFeb 17, 2026

Single Station Detection Yields Uncertain Location

Ah, then 20 tons fully coupled, no more than 400-800 tons fully decoupled. A one-station means its very hard to know the location with confidence.

By Jeffrey Lewis
Lop Nor 2.7‑magnitude Test Yields Mere
SocialFeb 17, 2026

Lop Nor 2.7‑magnitude Test Yields Mere

A magnitude of Mb=2.7 corresponds to about 18 tons of yield at China's Lop Nor test site. If the explosion was fully decoupled that would correspond to about 400-700 tons of TNT. Again, these are very small events, relatively...

By Jeffrey Lewis
Possible China Nuclear Test Detected, Seismology Needed
SocialFeb 16, 2026

Possible China Nuclear Test Detected, Seismology Needed

I wonder if this event is the alleged China nuclear test: 22 June 2020/0 depth/41.27, 90.75/~150 km from the test site, just outside error ellipse. The P/S amplitude ratio might show if it was an explosion--need a real seismologist for...

By Jeffrey Lewis
US Consensus on “Friendly” Proliferation Eroding, Prompting Pushback
SocialFeb 16, 2026

US Consensus on “Friendly” Proliferation Eroding, Prompting Pushback

The consensus that “friendly” proliferation is also bad is collapsing in the US, which is why we see efforts to shore it up, eg recent remarks by @USWPColby or the @NTI_WMD-@BelferCenter-@CarnegieEndow commission.

By Jeffrey Lewis