SIPRI Yearbook 2026: A Compounding Security Crisis
On June 9th, we did a brief commentary on the 2026 edition of the SIPRI Yearbook’s summary, which was published June 8th. Here we pull on some of the threads, point out patterns, and ask questions. This is an initial deep-dive before seeing where the full report takes us.
The Unraveling of Multilateral Institutions Is Self-Reinforcing
The US withdrawal from or defunding of UN bodies didn’t happen in isolation. Reduced UN peacekeeping budgets, stalled arms control negotiations, weakened Arms Trade Treaty (ATT) compliance, and the proliferation of middle-power “deal-making” diplomacy (Qatar, Türkiye, UAE) are symptoms of the same cause.
The system of multilateralism is losing the convening authority that made multilateral bargaining possible.
The Nuclear Risk Is Understated
SIPRI notes that warhead numbers continue declining. But look at it this way: dismantlement rates are slowing while new warheads are entering stockpiles. Combine this with nuclear-conventional entanglement (dual-capable missile systems increasingly indistinguishable in flight), the collapse of New START transparency measures, and the normalization of strikes on nuclear infrastructure (Iran this year and last).
The result? The risk environment has deteriorated faster than raw warhead counts suggest, making the number itself somewhat of a misleading metric.
Europe’s Rearmament Has Consequences
A 210% increase in European arms imports and military spending doubling since 2016 represents a fundamental reorientation of the European political economy. That in itself isn’t a bad thing. But it does have long-term implications SIPRI doesn’t fully unpack, at least in this summary document. One reason is that defense industrial capacity takes years to build.
As a result, European states are getting locked into procurement dependencies that will constrain fiscal policy for decades, regardless of the resolution of the Ukraine war.
The Technology Governance Gap Is Widening
The AI, cyber, and space chapters each document how governance frameworks are lagging behind capability deployment. Armed UAVs are becoming functionally indistinguishable from short-range missiles, yet no binding instrument governs them, for instance. AI is being actively deployed in targeting decisions in Gaza and Ukraine while international discussions remain at the “informal exchanges” stage. Space-based interceptors, (think Golden Dome) risk triggering arms race dynamics before the creation of any international governance framework.
The gap between capability and governance is compounding.
The Middle East as a Stress Test for International Law
Gaza and the Iran-Israel war together constitute something close to a controlled experiment in what happens when enforcement of international humanitarian law goes by the wayside. With 90% of Gaza’s population displaced, confirmed famine, and strikes on nuclear facilities despite widespread legal condemnation, 2025 could mark the point at which the practical deterrent value of IHL got downgraded.
That’s bad, because other actors will have noted this– and may act on it.
The Overarching Pattern
It has to do with norms.
The costs of defecting from international norms have fallen sharply, while the perceived benefits of unilateral or transactional action have risen. This reflects changes in the availability of alternative frameworks for peaceful resolution to conflict, as well as the erosion of the reputational mechanisms that have (imperfectly but mostly) enforced compliance.
The international security order is in transition. We don’t know exactly where we’re headed.
