Israel has strengthened its air defences in anticipation that the expected retaliation from Iran and its allies for the assassinations of two senior militant leaders will take the form of an airborne attack.
Tehran and its regional proxies, notably the Lebanon-based militant movement Hizbollah, have spent decades amassing a huge rocket, missile and drone arsenal that has stretched Israel’s much-vaunted defences to the limit over 10 months of war since Hamas’s October 7 assault from Gaza.
But Israeli officials expect that in the wake of the strike last week that killed Hizbollah commander Fuad Shukr in Beirut and the killing in Tehran of Hamas political chief Ismail Haniyeh the biggest test for the multi-layered array will come in the days ahead. Israel said it killed Shukr but has neither confirmed nor denied responsibility for the death of Haniyeh.
Much will depend on what kind of assault Iran, Hizbollah and other regional militias are planning.
“If it’s a mass combined attack, in a single barrage, at the same time . . . they could overwhelm the system to a certain degree,” said Yaakov Lappin, an Israeli military affairs analyst. “How many [projectiles] get through and what kind of damage [they] wreak is unknown.”
Israeli military spokesperson Daniel Hagari said this week that the country’s defences have been reinforced with extra personnel “in the air, at sea and on land” and set on the highest alert. But he also cautioned that the protective bubble provided by the state of the art Iron Dome system and several other platforms was “not hermetic”.
The fallibility of the system was highlighted last month, after a suspected Hizbollah rocket slammed into a football pitch on the Israeli-occupied Golan Heights, killing 12 children and sparking the most recent escalation in tensions.
Yet overall the Israeli public has grown confident in Iron Dome, the first layer of defence which has taken out thousands of shorter-range artillery rockets fired by Hamas and other Gaza-based Palestinian militant groups since it was introduced in 2011. Iron Dome, like Israel’s other air defences, was funded and developed jointly with the US military.
The Israel Defense Forces claimed a 90 per cent interception rate for projectiles fired by Hamas and other militants during the 2021 Gaza conflict at populated areas of the country.
It has not detailed the percentage of interceptions during the current conflict, although Hamas fired about 3,000 rockets at Israel at the onset on October 7. The system bent from the unprecedented barrage, likely the largest in a single day in military history, with at least 10 people killed, but it did not break.
Analysts say the high success rate is largely due to the platform’s sophisticated radar, now augmented with additional artificial intelligence capabilities, that enables it to discern in seconds which incoming rockets, within a roughly 70km range, are likely to land harmlessly on open ground and which could harm civilians or troops.
This also allows the IDF to conserve the finite supply of its more sophisticated Tamar interceptors, which cost tens of thousands of dollars per missile.
A sea-based version of Iron Dome, often referred to as C-Dome, is also deployed on Israeli navy corvettes, where it has successfully shot down attack drones fired at Israeli assets in the Red Sea by the Iran-backed Houthi militia and at Mediterranean gas rigs fired by Hizbollah.
Hizbollah possesses a much bigger and more sophisticated arsenal than Hamas or the Houthis. The militants are estimated to possess about 150,000 rockets and missiles, including long-range and precision-guided capabilities and attack drones, as well as anti-tank and anti-aircraft missiles. Much of this has been provided by Tehran, experts say.
Iran also has the Middle East’s “largest and most diverse missile arsenal”, according to the CSIS think-tank, made up of thousands of missiles, some capable of striking Israel and as far as south-east Europe.
To counter this threat, Israel developed a second layer of defence known as David’s Sling whose remit is to shoot down heavier rockets and tactical ballistic missiles, such as Scuds, in the range of 100km to 300km. The system, which went online in 2017, has only seen real action over the past year, with its Stunner interceptor missiles striking several projectiles fired from Gaza.
The third layer of air defence, Arrow 2 and 3, is intended to defend Israel from long-range ballistic missiles, intercepting incoming projectiles outside the Earth’s atmosphere, often high above and far away from Israeli airspace. The Arrow saw its first operational use during the current war, successfully shooting down a handful of incoming ballistic missiles from the Houthis and in April during a massive Iranian attack that included more than 100 ballistic missiles.
“The logic of the system is that one layer backs up the other,” said Lappin, the military analyst, and overall it has performed well, experts agree. Yet during the current conflict Israel has needed help.
Thwarting this Iranian barrage, the first direct attack by the Islamic republic from its own soil against Israel, necessitated the support of a US-led coalition, including the UK, France and Arab states, across the region of early-warning radar, missile defence platforms, and squadrons of fighter jets. A similar coalition has now been deployed again, providing Israel with another shield of protection, including against cruise missiles and attack drones.
That assault was telegraphed by Iran, giving Israel and its allies time to prepare their defences, with most of the projectiles destroyed before they crossed into Israeli airspace.
Yet Israel’s air defences are far from impregnable, with military analysts in particular highlighting the challenge posed by the lower-tech unmanned aerial vehicles fired by Hizbollah in the current conflict, which have proved difficult to detect, track and shoot down.
The slow-moving and agile drones have wreaked havoc across much of northern Israel, despite the best efforts of Iron Dome as well as US-built Patriot batteries and Israeli fighter jets to stop them. Hizbollah has also sent surveillance drones deep into Israel to capture footage of sensitive military sites. Projectiles fired by Hizbollah also have far less distance to travel to reach Israel than missiles fired from Iran.
Separately, a Houthi drone struck in the heart of Tel Aviv last month, killing one person, underlining the threat the Yemeni rebels could pose.
Tal Inbar, from the US-based Missile Defense Advocacy Alliance, said a big issue that Israel had not adequately prepared for was that Hizbollah was actively targeting its air defence and detection arrays.
Similarly, a huge synchronised assault by Iran and its allies — with attacks coming from different directions and in multiple forms — would be challenging for the Israeli systems to detect and track, Inbar warned.
“A multiplicity of targets and co-ordinated fire from a variety of arenas makes it difficult to create a ‘picture of the sky’,” he said, affecting the ability to shoot them down. “A clear working assumption is that there will always be more attackers than interceptors,” he added.
Deploying military-speak for what happens when missile barrages and drone swarms overwhelm a country’s defences, he told Israelis they should prepare for “greater spillage” than they are used to.
