Through trial and error, Iran found gaps in Israel’s storeyed air defences

The proportion of missiles that slipped through doubled during the 12-day war, data shows.

Israel’s recent war with Iran served as a cautionary tale for countries with sophisticated missile defences and those that seek to have them. Over 12 days, Iran pierced Israel’s defences with increasing success, showing that even the world’s most advanced systems can be penetrated.

While most of Iran’s missiles and drones were knocked down, Tehran changed tactics and found gaps in Israel’s armour through trial and error.

Tehran began to launch more advanced and longer-range missiles from a wider range of locations deep inside Iran, according to missile-defence experts who analysed open-source data and public images of missile fragments. The regime also altered the timing and pattern of attacks and increased the geographic spread of targets, the analysts found.

As the war went on, Iran fired fewer missiles, but its success rate rose, according to a Wall Street Journal analysis of data from think tanks based in Israel and Washington, DC.

In the first half of the conflict, 8 per cent of Iran’s missiles slipped through Israel’s defences. By the second half of the war, 16 per cent got past Israel’s interceptors, according to data from the Washington-based Jewish Institute for National Security of America, or Jinsa.

The Israeli flag flutters in front of a destroyed building at the site of an Iranian missile attack in Ramat Gan in central Israel near Tel Aviv last month. Picture: AFP

The success rate doesn’t take into account missiles that failed to launch or were intercepted before reaching Israeli airspace, said Mora Deitch, head of the Data Analytics Center at the Institute for National Security Studies at Tel Aviv University. Nor does it distinguish between missiles that were allowed to strike open areas in Israel and those that Israeli interceptors missed, said Deitch, whose think tank provided data on Iranian strikes and Israeli defence capabilities.

Iran’s most successful set of attacks came on June 22, two days before the end of the war, when 10 out of 27 missiles hit Israel, according to the Jinsa data. The data suggest that Iran successfully adapted “how, when and what” it was firing, said Ari Cicurel, associate director of foreign policy at Jinsa.

The Israeli military declined to comment on Jinsa’s figures beyond saying it doesn’t share specifics on interception rates.

Israel’s aerial defence — including the famed Iron Dome that intercepts short-range rockets from Gaza and Lebanon — is among the best in the world and was developed in partnership with the US.

“Any missile system, even a sophisticated one like Israel’s, will leak eventually,” said Raphael Cohen, a senior political scientist at Rand, created as a Pentagon think tank. “The key for any air-defence system is less that you build a perfect system with any one layer and more the cumulative effect.”

The remains of an Iranian missile lie near an Israeli settlement in the West Bank in the aftermath of the war. Picture: Menahem Kahana / AFP

An analysis of Israel’s public statements indicates that its interception rate declined over the course of the war. During the conflict, the Israeli military said it was intercepting 90 per cent to 95 per cent of Iran’s missiles. After the ceasefire on June 24, the military said it had intercepted 86 per cent overall.

In January, President Trump signed an executive order to develop the “Iron Dome for America,” a $US175 billion ($268bn) missile-defence system originally named after Israel’s array and now called Golden Dome, to protect the US from potential missile attacks. America’s size would make its skies much harder to defend than Israel’s.

Ukraine offers a better example of defending a large territory over a years-long war, but its air defences are a patchwork of American, European and homegrown technologies.

Israel’s advanced integrated system is more akin to what the US seeks to develop, Cohen of Rand said.

Israel’s own success at attacking Iranian missile launchers prevented Iran from deploying its older, less accurate and shorter-range missiles. But it also meant that Tehran reached for its more advanced and longer-range missiles sooner in the conflict.

Fragments of Iran’s hypersonic Fattah-1 missile fell in at least two Israeli towns, according to footage of debris analysed by missile experts.

The Fattah-1 descends at a sharp angle from outside the Earth’s atmosphere at over 10 times the speed of sound and features a warhead that detaches in flight and can dodge interceptors. Only Israel’s most advanced systems — the Arrow 3 and David’s Sling — can change course midflight to track it.

Iran also pivoted from firing large overnight barrages to launching smaller waves during daylight hours and from a wider variety of locations.

– A nurse carries medical supplies past a building with smoke billowing out after at Soroka Hospital after it was struck by an Iranian missile on June 19. Picture: AFP

Tehran further tested Israel’s interceptors by changing up its firing patterns, targeting far-apart cities and varying the intervals between attacks.

“They tried to separate the Israeli defence system,” said Yehoshua Kalisky, a missile-defence expert at INSS.

As the conflict wore on, a declining number of interceptors and their high cost would also have compelled Israel to conserve resources and only target missiles from Iran that posed the greatest threat, missile experts said.

Israeli and Iranian officials have independently called for reviews of their aerial capabilities.

“We are both on a learning curve,” said Kalisky, “they’re trying to improve their attacks, and we, our defence.”

Wall Street Journal