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US missile defence system Terminal High Altitude Area Defence (THAAD) became operational in Israel on Sunday, US Defence Secretary Lloyd Austin said. The development is seen as a potential escalation in the regional Iran-Israel crisis because 100 US soldiers will be deployed to operate it, potentially putting them in harm's way if Iran launches another missile strike.
Experts say the deployment is only one pillar of wide-ranging military co-operation, which helped Israel parry two massive Iranian ballistic missile attacks on April 13 and October 1. Both passed with a high percentage of missiles shot down and little damage to military or civilian infrastructure, but might have put strain on interceptor missile stocks.
Until now, much focus has been on US military material support for Israel – 45,000 tonnes of arms costing $17.9 billion in only one year. Likewise, the US and Israel have collaborated on jointly funded and produced missile defence systems, such as the Arrow Weapon System, since the 1990s.
But joint training for Iran’s recent attacks has been critical and was well established years before Hamas’s bloody October 7 attack on Israel – and the retaliation that has destroyed most of Gaza – brought Iran and Israel to direct confrontation.
About 1,200 people in Israel, mostly civilians, were killed in the attack, and 42,500 Palestinians, also mostly civilians, have been killed in the war in Gaza.
Building a missile shield
“Bilateral training is critical and the US and Israel have been executing this for decades,” says David Shank, former commandant of the US Air Defence Artillery School.
“The highlight of the bilateral training is an Integrated Air and Missile Defence exercise called Juniper Cobra, which has been ongoing since the late 1990s. This exercise includes US Army Air Defence Artillery forces deploying with equipment to designated locations, as well as senior leaders to work alongside the Israeli Defence Forces and Israeli Air Defence Forces,” says Mr Shank, who also commanded the US 10th Army Air and Missile Defence Command in Europe.
“All US and Israeli air and missile defence systems are integrated into one networked architecture with fires being directed from the Air Operations Centre. These forces also include US Navy Aegis destroyer ships which possess the SM-3 and SM-6 missiles and work in tandem with the THAAD weapon system’s capabilities,” he says.
The US and Israel held their last joint exercise in September last year, which focused on countering a massive missile barrage. The THAAD system was used for a previous joint drill in 2019. Such training has played a role in Centcom, the US military headquarters for the Middle East, integrating Israeli missile defences into its own defensive shield.
“Training missile defence crews is very, very important,” says Carl Rehberg, a non-resident senior fellow at the Centre for Strategic and Budgetary Assessments think tank.
“This is not realised by most, as almost everyone gets infatuated with just the technology. Air defence artillery crews are some of the most highly trained personnel in the US military,” says Mr Rehberg, who has taught courses at the US National Defence University and the US Air Force Academy, as well as working on long-term US military strategy.
As part of training co-operation, the US had previously integrated THAAD’s powerful ground radar, the AN/TPY-2, which can detect targets thousands of kilometres away, with Israeli defences. Joint training has recently involved the Israeli Test-Bed Battle Lab system for simulating missile attacks, developed by Israeli company Elbit.
Experts say integrated ballistic missile defence not only involves radar networks of radar to monitor for missiles over vast areas, but also space-based detection and early warning.
A THAAD radar has been stationed on top Mount Har Keren in the Negev desert since 2012, boosting its already formidable range from a 370 metre high vantage point, giving Israel greater situational awareness of the Iranian ballistic missile threat.
“The THAAD radar is the main point here, because for the interceptors themselves, there are constraints on manufacturing them,” says Noam Ostfeld, a defence analyst with UK risk consultancy Sibylline.
“It takes time, it takes money, and stocks have been depleted. In terms of radar, THAAD is among the best systems for identifying targets at vast ranges.”
The radar has greatly boosted the Israel air defence's current detection capability – Arrow’s Green Pine radar, which it is claimed has a range of 500km.
The full THAAD battery deployment, including a second radar, following the radar deployment at the US base Site 512 in the Negev, is a step up.
Setting up the system is a feat in itself. At the most basic level, lorry-mounted missile launchers and a radar system are flown to the theatre of operations and set up at the firing site, where defensive earth berms are built. The main components are then connected, including the fire control unit, which communicates with missile interceptors and other air defence batteries, while crunching data about targets.
The different elements are connected by fibre optic cable to co-ordinate against rapidly emerging threats. Iran’s missiles take only 12 minutes to reach Israel.
THAAD’s radar alone weighs 34 tonnes and requires a cooling unit pumping 1,000 litres of cooling fluid per minute. That is necessary because of the heat generated by the radar, powered by a 1.1 megawatt diesel generator, enough to power nearly 1,000 homes, and guzzling 340 litres per hour to produce 4,160 volts. All radar has antennae for sending and receiving radio waves – THAAD's has 25,000.
THAAD crews are drilled on setting up this equipment rapidly in far-flung combat zones at a moment’s notice, or taking it down within hours. In the Israel deployment, it took only days to get up and running. Operators require about six months of training. One officer there said operators must be “extremely knowledgeable” of different weapons systems and their capabilities, not merely THAAD.
Crews are certified for combat, after examiners watch the drill, known as Table VIII evaluation. Air defence crews are continually tested on various scenarios and aspects of the system – Patriot missile battery crews are said to be tested daily and THAAD is probably no different. This applies not only to crews operating radar and fire control computers, but also to logistical support personnel who provide 24-hour maintenance and conduct daily checks on the equipment.
“My unit, 10th AAMDC, was responsible for the IAMD defence of Israel,” Mr Shank says.
“During this timeframe, then Secretary of Defence Mattis implemented a programme known as ‘Dynamic Force Employment’, DFE for short. The intent of the DFE was to demonstrate the US ability to rapidly deploy to multiple locations. The first DFE included the deployment of a THAAD weapon system to the State of Israel. This was a monumental event.”
Critically, crews are meant to operate in tandem with nearby air defences that hit targets at lower levels and trajectories – in the case of Iran’s strikes on Israel, Israeli Arrow 2 and 3 interceptor batteries and David’s Sling, which counters lower-altitude missile threats.
That the US is deploying THAAD to Israel is a measure of Washington’s concern over a Middle East conflagration spreading, with retaliation followed by counter-retaliation. The US is understood to possess only seven THAAD batteries, each made up of six lorry-mounted launchers that carry eight interceptors.
The system is also costly, estimated at $1.25 billion per battery and with each missile costing $12.6 million. THAAD is capable of striking incoming ballistic missiles head-on at ranges of 200km, with near 100 per cent accuracy in testing. It is claimed the 900kg missiles reach eight times the speed of sound on their way to intercept threats, sometimes outside of the Earth’s atmosphere.
Space Force early warning
One aspect of this joint effort to detect missiles and cue up launchers occurs in space – at least for the Americans but probably for the Israelis, too – relayed to Centcom and passed on to THAAD and other missile defence systems such as Aegis, the US naval interceptor system used from the Mediterranean during both Iranian attacks.
The Space-Based Infrared System (SBIRS) consists of six 2,500kg satellites, 35,000km above Earth, that take infrared images of the planet every 30 seconds to detect ballistic missile launches. Israel is rumoured to benefit from the $20 billion system but Mr Rehberg says this is likely.
SBIRS is operated by Space Force, a branch of the US military created in 2019 to operate communications and early warning satellites, among other tasks.
“Space Force has become increasingly important over the years as their capabilities have increased dramatically,” Mr Rehberg says. “There are multiple ways to determine this information and depending on a number of factors, space sensors would likely be early detectors.”
Thomas Harding contributed to this report from London.
