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Iran Conflict 2026
26MAR

Interceptor Crisis Reaches Projected Depletion Window

2 min read
09:36UTC

THAAD exhaustion may have arrived silently. Arrow-3 stocks at 81% depletion. JASSM-ER reserves for a Taiwan contingency spent in Iran.

ConflictDeveloping
Key takeaway

Defence and strike stocks deplete simultaneously; production cannot catch either.

The Royal United Services Institute projected in early March that THAAD stocks would exhaust within one month; that window has now closed . The Payne Institute estimates one-third of the THAAD stockpile has been consumed. Annual production capacity: roughly 100 interceptors. No emergency resupply has been announced.

Arrow-3 stocks remain at 81% depletion or worse . Combined with the consumption of more than 1,000 JASSM-ERs drawn from Pacific Command stocks , the US is simultaneously drawing down its primary standoff strike capability and its missile defence inventory. The restock gap for JASSM-ERs runs 18 to 30 months under even surge production. The weapons designed for a Taiwan contingency are being spent in Iran.

The arithmetic runs one direction. Iran does not need to win the air war. It needs to outlast the interceptors. With Russia supplying an estimated 1,000 Geran-2 drones per day , the attritional equation favours the side that can produce munitions at industrial scale against a defence architecture that cannot replenish at any scale.

If THAAD and Arrow-3 stocks cross critical thresholds without resupply, the US and Israel face a binary choice: accept degraded air defence or reduce the operational tempo that is consuming the interceptors. Either path changes the war's trajectory.

Deep Analysis

In plain English

The missiles that defend against Iranian attacks are running out, and the factories that make them produce too slowly to catch up. At the same time, the cruise missiles being used to attack Iran were originally set aside for a possible conflict with China, leaving the Pacific less defended. Iran does not need to win; it needs to keep firing until the defences run dry.

Deep Analysis
Root Causes

The US defence-industrial base was optimised for precision and quality over volume. Annual production rates (100 THAAD interceptors, 396 JASSM-ERs at standard rate) assumed deterrence and short, decisive conflicts, not a sustained attritional war against an adversary supported by Russian industrial-scale drone production.

Escalation

Structurally escalatory. As defensive stocks deplete, the risk of successful Iranian strikes on Gulf energy infrastructure increases. This could trigger oil price spikes, Gulf military responses (under the Article 51 framework), or US escalation to compensate for degraded defence with increased offensive operations.

What could happen next?
  • Missile defence architecture protecting Israel, UAE, and US forces degrades materially by mid-to-late April

    weeks · Assessed
  • JASSM-ER depletion weakens US deterrence posture against China through at least mid-2028

    years · Assessed
  • Degraded air defence increases risk of successful strikes on Gulf energy infrastructure

    weeks · Suggested
First Reported In

Update #60 · Pakistan's Ceasefire Plan Fills the Vacuum

Defence Security Asia / RUSI· 6 Apr 2026
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Different Perspectives
IAEA
IAEA
Director General Rafael Grossi appeared in person at the UNSC on 19 May and warned that a direct hit on an operating reactor 'could result in very high release of radioactivity'. The session produced a condemnation record but no resolution, and the Barakah perimeter was already struck on 17 May.
Hengaw (Kurdish rights monitor)
Hengaw (Kurdish rights monitor)
Hengaw documented three judicial executions and the detention of Kurdish writer Majid Karimi in Tehran on 19 May, establishing Khorasan Razavi province as the newest geography in Iran's wartime judicial record. The organisation's Norway-based operation continues to surface a domestic repression track running in parallel with every diplomatic and military development.
India
India
Six India-flagged vessels conducted a coordinated cluster transit under PGSA bilateral assurances during the 17 May window, paying no yuan tolls. New Delhi's inclusion in Iran's state-to-state passage track insulates Indian energy supply without requiring endorsement of the PGSA's yuan-toll architecture or alignment with the US coalition.
Pakistan
Pakistan
Pakistan is the only functioning diplomatic bridge between Tehran and Washington. Its role is relay, not mediation in the settlement sense: it conveyed Iran's 10-point counter-MOU in early May, relayed the US rejection, and is now passing 'corrective points' in the third documented exchange of this sub-cycle without either side working from a shared text.
UK and France (Northwood coalition)
UK and France (Northwood coalition)
Twenty-six coalition members have published no rules of engagement eight days after the Bahrain joint statement; Lloyd's underwriters have conditioned war-risk reopening on written ROE from either Iran or the coalition. Italian and French mine-countermeasures deployments are operating on the in-water clearance task CENTCOM Admiral Brad Cooper's 90% mine-stockpile claim does not address.
Saudi Arabia
Saudi Arabia
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