Israel versus Iran: What all-out war could look like (2024)

Open warfare between Israel and Iran is a real possibility again. Israel is bracing itself for an attack by Iran, which has vowed to retaliate for the July 31 killing in Tehran of the political chief of Palestinian group Hamas.

The conflict between Israel and Iran had been on a low boil for decades, with the two sides attacking each other mostly quietly and, in Iran’s case, often by proxy.

But the outbreak of war between Israel and the Iran-backed Hamas in October 2023 has accelerated hostilities.

The two came to direct blows in April, when Iran launched a massive missile and drone attack on Israel. While it caused minimal damage and provoked a more limited return attack, the head-to-head fighting moved the Israel-Iran conflict into a more dangerous phase.

How do Israeli and Iranian military capabilities compare?

Israel’s forces have a vast technological edge over Iran’s. This is partly down to military and financial support from the US, which has long sought to ensure Israel’s advantage as part of its commitment to the Jewish state’s security.

For example, Israel is the only state in the Middle East so far that has bought Lockheed Martin’s F-35 fighter jet – the costliest weapons system ever.

Israel is also widely believed to have nuclear weapons, though it has never acknowledged that capability.

By contrast, sanctions and political isolation have hobbled Iran’s access to foreign military technology, driving it to develop its own weapons, including the missiles and drones it fired against Israel in April.

Iran’s combat aircraft are mostly older models inherited from before the country’s 1979 revolution. It has agreed to buy Russian jets, but it is not clear whether these have been delivered.

Iran has long been suspected of harbouring the goal of using its nuclear programme to build nuclear weapons, though it denies having such an ambition.

It has accumulated enough enriched uranium to construct several nuclear bombs, should its leaders choose to purify the heavy metal to the 90 per cent level typically used in such weapons. It would still have to master the process of weaponising the fuel to produce an operable device capable of hitting a remote target.

Though at a technological disadvantage, Iran’s military is thought to have a significant stockpile of the ballistic and cruise missiles and cheap unmanned aerial vehicles, or drones, that it deployed against Israel in April.

As Iran learnt in that attack, penetrating Israel’s substantial air defences is a challenge. There is getting past Israeli Air Force fighters. Then there are Israel’s Arrow and David’s Sling air defence systems, which, together with US and other allied forces in the region, intercepted 99 per cent of the more than 300 drones and missiles that Iran fired, according to Israel’s military.

Iran’s own defensive arsenal includes surface-to-air missile systems, such as Russia’s S-300, to counter aircraft and cruise missiles and the locally made Arman anti-ballistic missile system. These are not nearly as battle-tested as Israel’s defences – a testament to Iran’s preference for asymmetric warfare, where it can project outsized power, over head-to-head combat.

Iran accidentally shot down a Ukrainian passenger aircraft in 2020 amid heightened tensions with the US using a Russian-made Tor air defence missile.

Both Israel and Iran have cyberwar capabilities. More than a decade ago, malware known as Stuxnet compromised operations at an Iranian nuclear enrichment facility in what is suspected to have been a US and Israeli operation.

Iran is capable of “a range of cyber operations, from information operations to destructive attacks against government and commercial networks worldwide”, according to an assessment by the US Defence Intelligence Agency released on April 11.

Cyber attacks launched by Iran include a hack that sought to cripple computers and water flow for two Israeli districts, according to the Council on Foreign Relations.

Would Israel target Iran’s nuclear sites?

An Israeli air attack on Iran’s nuclear programme would be one of the most extreme responses to a new Iranian assault. Previously, Israel has reserved that threat for a time when Iran reaches the brink of nuclear weapons capability.

The challenge is that the Islamic Republic’s atomic sites are numerous and dispersed around the country.

The most important have been moved underground in recent years in an effort to put them out of harm’s way, though that has not stopped smaller-scale sabotage operations that are routinely attributed to Israel.

Israel is widely thought to have been behind the assassination in Tehran of five Iranian nuclear scientists since 2010. In 2021, Iran blamed Israel for an explosion at a key enrichment facility.

A senior military official responsible for protecting Iran’s nuclear programme said in April that the country would retaliate in kind if Israel targeted the programme.

He hinted that even the threat of doing so could push Iran to reconsider its policies around what it describes as a peaceful nuclear programme.

Who are their allies?

Iran’s most important allies are the Shi’ite militias in Lebanon, Yemen, Iraq and Syria that it supports with money, weapons and training.

The Lebanese militia Hezbollah would be positioned to play the most significant role in an all-out war.

It has fought repeated battles with Israel and has been regularly firing missiles, mortars and rockets into northern Israel since war broke out between Israel and Hamas.

Hezbollah’s arsenal contains more than 70,000 rockets and missiles, including long-range and precision-guided missiles, according to Israeli intelligence.

Yemen’s Iran-backed Houthi rebels would likely be eager to play a part in a larger war.

Since the start of the Israel-Hamas war, the Houthis, in addition to attacking commercial ships in the Red Sea, have been firing ballistic missiles and drones at Israel. On July 19, a Houthi drone hit a building in central Tel Aviv, killing a man and injuring several others, the first deadly attack of its kind on Israel’s soil.

Iran’s only state ally in the Middle East is Syria. The government of President Bashar al-Assad would be unlikely to be of assistance given that it is still struggling to gain control over the entire country following the outbreak of civil war in 2011.

Iran has good relations with Russia, though Moscow’s war in Ukraine would likely limit its ability to help, and with China, which has bought Iranian oil though it remains sanctioned by the US and allies.

Israel has the US and Britain on its side. Forces from the two countries destroyed some of the missiles and drones that Iran launched at Israel in April.

Anticipating a new Iranian attack on Israel, the US military has announced steps to beef up its presence in the Middle East, adding ships, fighter planes and ballistic missile defence vessels.

How might Arab states react?

An Israel-Iran war would put many of the countries in the region in a difficult position.

Four Arab countries made peace deals with Israel in 2020 via the so-called Abraham Accords. Their distrust of Iran was part of what brought them together.

But it is unlikely that any Arab state would stand with Israel in a confrontation against a fellow Muslim country, let alone one as powerful as Iran.

Iran and Saudi Arabia in 2023 restored diplomatic relations after a seven-year freeze.

Saudi Arabia has been exploring the possibility of normalising ties with Israel as part of a broader deal in which it hopes to attain US security guarantees, and it would likely try to avoid becoming embroiled in the conflict. BLOOMBERG