Israel’s Iron Dome system overwhelmed on October 7, inquiry reveals

Troops were unable to reload interceptors fast enough while Hamas invaded

Israel's Iron Dome intercepts missiles launched from the Gaza Strip on October 11, 2023, which it had failed to do four days earlier. EPA

New details have come to light on the failure of Israel’s Iron Dome defence system during the Hamas-led assault on southern Israel on October 7, 2023.

According to an Israeli military inquiry, details of which were reported to Israel's Channel 12 news, about half of 3,700 rockets fired by Hamas in the first four hours of the offensive made it past the defensive system.

While the failure was previously thought to be technical, a major problem was replenishing the interceptor missiles used by the system, according to the report.

In previous conflicts, the Iron Dome, which has a range of up to 70km and is used primarily to shoot down unguided rockets, which often have a shorter range, was thought to be 90 per cent effective.

During exchanges of fire in the summer of 2021, the system is thought to have shot down 735 of 800 rockets and mortar shells it identified as threatening populated areas, the Centre for Strategic and International Studies think tank found.

Rockets fired by Hamas and other militant groups in Gaza, meanwhile, are typically inaccurate – about 4,500 were fired in the same period and the Iron Dome is designed to ignore those heading for open, less-populated areas. It makes these calculations in seconds and the system as a whole, including radar and a "fire control" computer, is claimed to be able to assess more than 1,000 airborne targets at once.

But experts say a sudden “saturation” attack of thousands of projectiles could overwhelm the system by exhausting interceptors rapidly. One Israeli security expert previously told The National this was one reason why the Israeli military had dedicated much of its planning and intelligence capacity to countering Hezbollah in Lebanon, which had a far bigger arsenal of rockets than Hamas.

This lack of attention to Gaza, which aided Hamas's October 7 plans and meant the "most successful attack" on Israel came from the enclave, rather than Lebanon, where Hezbollah was thought to possess five times more rockets (up to 150,000) than Hamas.

Each Iron Dome battery can fire about 20 Tamir interceptors before it needs reloading. This was the critical shortfall, the Israeli inquiry found, because during the Hamas-led invasion, army units could not safely resupply the system and some forces were ambushed while trying to do so.

About 1,200 people were killed on October 7, with 21 villages were captured and an estimated 250 taken hostage. The incursion, thought to have involved between 2,000 and 4,000 fighters from Hamas and allied groups, was intended to hold territory, which led to a series of bloody battles within Israel.

Previous inquiries found that Israel’s initial ground response was highly disorganised. Hamas succeeded in destroying military communication relay sites, while the shock of the assault led to ad hoc groups of security forces intervening without proper planning. Hamas fighters were eventually pushed out of Israel within about three days of the initial attack.

Israel responded by dropping about 6,000 bombs on Gaza within a week. More than 47,400 Palestinians, mostly civilians, were killed in Israeli bombardment and ground operations before a ceasefire began on January 19.