Iron Dome vs David’s Sling vs Arrow: Which Layer Actually Stops Iran’s Ballistic Missiles?

The top layer did not fight alone. JINSA’s analysis of launch footage extrapolated to 21 Arrow 2, 80 Arrow 3 and 92 US THAAD interceptors for the whole war, with THAAD covering almost half “perhaps because of Israel’s insufficient Arrow interceptor capacity”. US officials later told The Wall Street Journal the Army fired more than 150 THAAD rounds, nearly a quarter of all the interceptors the Pentagon had ever bought, and Navy ships added about 80 SM-3s, The War Zone reported.

IAI chief executive Boaz Levy told Business Insider that Arrow hit at least 90% of what it engaged, a company figure. Iron Dome and David’s Sling launched too, but the ministry credited the lower tiers mainly with the 99% drone kill rate. That division of labour did not survive 2026.

The second war began on 28 February 2026, and interceptor stocks became a command decision. On the evening of 21 March two Iranian missiles hit residential areas of Arad and Dimona, wounding more than 100 people, medics said; the military confirmed to AFP on 23 March that David’s Sling had malfunctioned. Calcalist, which broke the story, reported that commanders had assigned the engagement to David’s Sling after its February upgrade in order to preserve Arrow stocks for a long war.

The Air Force identified the missiles as Qadr types and said the failure was not systemic, since the same system had intercepted similar missiles before, Calcalist reported. The military still claimed 92% interception of the roughly 440 missiles fired by then, above the 2025 rate. A mid-tier system built against Hezbollah’s heavy rockets was now the first line against medium-range ballistic missiles, and each miss lands on a town.

The difference is altitude and price. Iron Dome’s Tamir is a small interceptor for rockets, mortars and drones inside roughly 70 km; CSIS puts its cost at about $40,000 to $50,000, with up to 20 rounds on each of a battery’s three or four launchers. David’s Sling’s Stunner has no warhead and rams its target at 40 to 300 km, which suits cruise missiles and the heaviest rockets; CSIS cites a Haaretz estimate of about $1 million each, and Calcalist says it costs roughly half of a higher-tier shot.

Arrow 2 detonates a fragmentation warhead near a re-entering warhead at up to 50 km altitude. Arrow 3 kills it in space before re-entry; JINSA puts both Arrow rounds at $2 million to $3 million. US THAAD costs $12.7 million to $15.5 million per round. Only Arrow, THAAD and the Navy’s SM-3 were designed for the medium-range ballistic missiles Iran fires.

JINSA’s assumptions put an Emad at about $250,000 and a Ghadr at about $5 million, so a 100-missile salvo costs Tehran between $25 million and $500 million. If Israel fires two Arrow rounds at each, the bill is $400 million to $600 million. Calcalist says IAI has tripled Arrow 3 output compared with prewar levels, and the Pentagon moved in January 2026 to lift THAAD production from 96 to 400 a year, according to a New York Times report. The alternative, rationing Arrow and pushing David’s Sling up the altitude ladder, is what Arad and Dimona paid for. Gulf capitals that watched the Riyadh airport strike face the same arithmetic with thinner stocks.