22OCT

Arrow-3 stocks hit 81 per cent drain

2 min read

17:22UTC

RUSI data shows the missile shield protecting Israel and the UAE will be materially degraded by mid-April. Rebuilding takes years.

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ConflictDeveloping

Key takeaway

Iran does not need to win the air war; it needs to outlast the interceptors.

RUSI's "Command of the Reload" report documented 11,294 munitions expended in the campaign's first 16 days at an estimated cost of $26 billion. Arrow-3 interceptors are at 81% depletion by end of March. THAAD stocks are "approximately one month or less" from exhaustion at current expenditure rates.⁠¹

Replenishment is not a logistics problem; it is an industrial one. A single Arrow-3 interceptor costs $2 to $3 million and takes months to produce. Full stock rebuild: two to three years. The missile defence architecture protecting Israel, the UAE, and US forces will be materially degraded by mid-to-late April.

Deep Analysis

In plain English

The US and Israel have been intercepting Iranian missiles and drones using expensive specialist rockets called interceptors. Each intercept uses one up. RUSI, a respected defence think tank, calculated that Israel's best interceptors are 81% exhausted. The US's top-tier system, THAAD, is roughly one month from running out. Each interceptor costs $2-3 million and takes months to produce. Rebuilding the full stock takes 2-3 years. Iran does not need to win the air war; it just needs to keep firing until the defensive rockets run out.

What could happen next?

Risk
Arrow-3 exhaustion in mid-April degrades Israeli protection against Iran's long-range ballistic missiles at the moment THAAD is also near exhaustion.
Consequence
Interceptor depletion creates a forcing function for all other deadlines: the 6 April grid deadline, the Kharg timeline, and the War Powers clock all operate inside a window shaped by shield degradation.

Source Landscape

This story draws on neutral-leaning sources

Primary parallel: The Soviet attritional strategy in Afghanistan (1979-89) succeeded not by defeating the Mujahideen militarily but by exhausting the adversary's will and resources. Iran's missile-drone strategy applies the same logic to defensive munitions rather than offensive will: exhaust the interceptors, then strike through the degraded shield.

Counter-parallel: The 1973 Yom Kippur War's early days saw Israeli munitions near depletion before a US emergency resupply reversed the trajectory. No comparable resupply mechanism exists for Arrow-3 or THAAD interceptors at the scale and speed required here.

A single Arrow-3 interceptor costs $2-3 million and takes months to build. Full Arrow-3 stock rebuild: 2-3 years at current production rates. THAAD annual production is approximately 48 interceptors; the entire global THAAD arsenal was 25% depleted in the first eight days.

The $26 billion estimated 16-day campaign cost reflects this asymmetry: Iran fires Shaheds at $20,000-50,000 each; the US intercepts with THAAD and Arrow-3 at $2-3 million each. Iran sustains the exchange rate indefinitely with Russian industrial supply; the US cannot.

Consensus view: RUSI's 'Command of the Reload' report documented the attritional dynamic that multiple US defence analysts had flagged since early March. The Center for Strategic and International Studies estimated the first 100 hours of operation at $3.7 billion, with munitions costs dominating. The production-versus-consumption gap is structural: Lockheed Martin produces approximately 48 THAAD interceptors per year.

Counter-view: US officials have suggested emergency production surge authority could accelerate output. Israel's NIS 2.6 billion emergency procurement indicates awareness of the depletion problem and efforts to address it before exhaustion.

Key tension: Production surge takes months to yield interceptors. The shield degrades in weeks. The gap between production timescale and depletion timescale is the strategic asymmetry Iran is exploiting.

Sources:Pentagon / The Intercept / Novara Media

Mentions:RUSI →Afghanistan →Center for Strategic and International Studies →Iran →Yom Kippur War →Lockheed Martin →Israel →Arrow-3 →THAAD →

First Reported In

Update #58 · First US aircraft fall over Iran

Pentagon / The Intercept / Novara Media· 4 Apr 2026

Read original →

Causes and effects

Caused by

UAE Stops 2,469 Missiles and Drones

The sustained intercept rate consuming Arrow-3 and THAAD stocks is the underlying cause of the depletion crisis RUSI documented.

Occurred 1 Apr 2026

Read story →

This Event

Arrow-3 stocks hit 81 per cent drain

Interceptor depletion is the hidden clock governing every other deadline in this conflict.

Led to

Iran War Burns Through Pacific Missile Reserves

Arrow-3 at 81% depletion and THAAD within one month of exhaustion form the missile defence context in which the JASSM-ER Pacific stock depletion compounds overall US munitions crisis.

Occurred 4 Apr 2026

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Interceptor Crisis Reaches Projected Depletion Window

Arrow-3 at 81% depletion and THAAD one month from exhaustion (ID:1935) projected thresholds now appear to have been reached.

Occurred 6 Apr 2026

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Different Perspectives

Wang Yi

China's foreign minister and Djibouti's issued a joint communique on 21 October saying the war should not reach the Horn of Africa and stressing free navigation through Bab al-Mandeb. The text names neither Iran nor the Houthis, and Djibouti hosts China's only overseas military base, opposite the Yemeni coast.

Ministry of External Affairs

India's foreign ministry called the attacks on Saudi civilian and energy sites "unacceptable" on 22 October and said they must stop at once. An Indian died at Dammam, Indians were injured there and at Shaybah, and about 4,000 Umrah pilgrims remain stranded by one MP's count.

Iraq

Iraq closed the al-Sheeb crossing with Iran to travellers and trucks from 21 October and said other crossings would close gradually. Unlike September's closure, which ended on a staged timetable, this one has none, and Iran's interior ministry said it received no notice.

Abdel Fattah el-Sisi

Egypt's president said on 21 October that Cairo's support would "defend Saudi territory, and does not include an attack on Yemen". Araghchi warned that Egyptian involvement would further complicate the situation, and Cairo's limit matches the one Ankara set on 8 October against attacking another state's soil.

UK Ministry of Defence

The MoD said on 20 October that RAF Typhoons over Saudi Arabia will not strike the Houthis, but extended tanker support to Saudi operations including against Houthi targets in Yemen. The tanker line sets no limit on strikes, so British aircraft may now refuel Saudi jets on bombing runs.

Turkey

Ankara sent the Mecca Joint Defence Agreement to parliament around 20 October, and its published text treats an attack on one party as an attack on all. Article 16 brings it into force only on the last ratification, so the 5 October invocation in Riyadh could not yet bind Turkey.

Written with AI from Lowdown's published reporting. Not individually reviewed by an editor. Editorial standards.