Iran’s widely anticipated missile and drone attack was defeated with the orchestrated help of the US, UK and Jordan who, alongside the Israeli military, ensured that all but a handful of ballistic missiles were neutralised overnight. The Israel Defense Forces (IDF) said on Sunday that about 360 missiles and drones were fired from Iran and that “99% of the threats” had been intercepted in a successful defence mission that may have cost Israel £800m – but will have saved many lives and dented Iran’s military credibility. Iran’s plan appears to have been to try to overwhelm Israel’s system of air defences with a complex attack of the type employed by Russia against Ukraine, but on a much vaster scale. It comprised relatively slow-moving drones, faster cruise missiles and high-speed ballistic missiles capable of travelling several times quicker than the speed of sound. Though the attack was well telegraphed, with Iran’s foreign minister, Hossein Amir-Abdollahian, saying on Sunday it had given neighbouring countries 72 hours notice, its size was notable. Roughly three times a large-scale Russian assault in Ukraine and comprising over 100 ballistic missiles, the assault was a serious threat to any air defence system. Iran’s chief of general staff, Gen Mohammad Bagheri, said on Sunday that the operation was considered a success and further attacks on its part were not necessary – but while Tehran will have learned about Israel’s air defences, the apparently low impact rate, particularly from the missiles, is likely to be a disappointment. By comparison, the surprise drone and missile attack on two Saudi oil installations at Abqaiq and Khurais in September 2019, orchestrated by Iran, temporarily knocked out 5% of the world’s oil supply. Estimates vary, but two or three dozen drones and missiles were used at the time. “Look at the size and scale of this latest attack – this was not a salutary move. It was designed to inflict real damage, but the fact that it didn’t is damaging to Iran’s credibility,” said Sidharth Kaushal of the Royal United Services Institute thinktank. Overnight, international help was critical in eliminating the slower-moving drones: the US said it had knocked out about 70 drones and three missiles. The UK prime minister, Rishi Sunak, added that the RAF had intercepted an unspecified number. Other reports indicated Jordan, a longstanding US ally, had shot down dozens more drones over its airspace. Working together to eliminate drones and cruise and ballistic missiles would have required careful planning, Kaushal added. “This is complex in every way. The defenders were a multinational force, having to operate in a deconflicted way, facing a mixture of weapons with different flight characteristics, from slower-moving drones to high-altitude ballistic missiles.” Israel’s military said all 170 drones launched from Iran, likely to be from its Shahed family, were shot down before they reached Israeli airspace. In themselves, the drones are not much threat, able only to carry a modest bomb of up to 50kg, but their intention is to tie up defenders. Videos of the craft, circulated on social media hours before being shot down, gave those responding plenty of time to react. The noisy engines suggested they were the slow-flying Shahed-136, which would take six hours to fly from Iran to Israel, although some Israeli media reported Iran had launched the faster jet-engined Shahed 238, which travel three times more quickly and whose flight time matched the events overnight. Though the participation of countries other than the US may have been a surprise overnight, there was plenty of time to plan. It is 10 days since the US first warned about a response from Tehran, and the US and UK had been moving military assets into the Middle East to prepare since then. On Friday the US said it had shifted assets to the region, but declined to give further details, while the UK enhanced the RAF presence at the Akrotiri airbase in Cyprus. Planning was in place at the end of the week, with the prime minister, Rishi Sunak, saying on Sunday he had signed off Britain’s involvement at a Cobra emergency meeting two days earlier. Israel said Iran also launched 30 cruise missiles towards its territory, with IDF jets intercepting 25 “outside the country’s borders”, according to military spokesperson Daniel Hagari. The missiles are most probably the newly designed Paveh-351, designed to be manoeuvrable in flight but still taking two hours from Iran. The most serious threat came from high-speed ballistic missiles, capable of flying several times the speed of sound and making the journey from Iran to Israel (about 600 miles at the closest points) in less than 15 minutes. More than 120 were launched at Israel, Hagari said, and he acknowledged that “a few” crossed into Israel’s airspace, some striking at the Nevatim airbase. Tackling these was largely the task of Israel’s air defence system, which relies on rockets to hit incoming missiles. Knocking out the ballistic missiles was primarily the task of the Arrow 2 and Arrow 3 systems, manufactured in an Israeli-US collaboration but never used until the start of the Israel-Hamas war, supported by David’s Sling, a medium-range interceptor. Brig Gen Reem Aminoach, a former financial adviser to the IDF chief of staff, told Israel’s Ynet News that an Arrow missile typically costs $3.5m (£2.8m) a time, and David’s Sling interceptors $1m (£800,000). Adding up the cost of eliminating 100 ballistic missiles, plus the costs of the whole air defence campaign, is “an order of magnitude of 4 to 5 billion shekels (£850m to £1.1bn)”, he estimated. However, the attack was also expensive for Iran, with ballistic missiles generally costing upwards of £80,000. The US estimates Tehran had about 3,000, the largest arsenal in the Middle East.