Was Iran behind Hamas’s onslaught on Israel? According to the Wall Street Journal (8 October) which only quotes anonymous sources from Hamas and Hizbullah, Tehran gave the green light for ‘Operation Al-Aqsa Flood’. Iran’s leaders deny this, while praising the Hamas attacks and urging ‘continued resistance’ to Israel. In the US, a number of Republican and Democratic politicians have called for fresh sanctions on Iran.

There’s just one question: if the Islamic Republic was behind the attack, why didn’t Hizbullah, its main ally in the region, enter the war at the same time as Hamas by way of ‘presenting a united front’ or of ‘common resistance’, as Hizbullah’s leaders like to put it? That would have helped create disorder in the Israeli army (IDF), which has several units deployed in the West Bank – even before the US sent the aircraft carrier USS Gerald R Ford and its strike group to cruise off the Israeli coast as a ‘precautionary measure’.

If Iran knew of the offensive beforehand, it may not have known the details, especially the date and time. A number of Arab analysts favour this scenario, with Hamas taking the decision to launch the attack alone, without warning its allies. They suggest that its military wing, headed by Mohammed Deif, planned the operation without reference to Tehran, or even to Hamas’s own political leaders in exile in Qatar. This would have avoided leaks but also, importantly, asserted the primacy of the ‘inside’ leadership in Gaza.

The other possibility is that Iran didn’t want Hizbullah to be involved too early, and was keeping it in reserve until it saw how events unfolded. Tehran sees Hizbullah’s presence as deterring Israel from attacking its own nuclear installations, and wouldn’t involve it without careful consideration. The Islamic Republic hesitated before encouraging Hizbullah to intervene in the Syrian civil war on the side of Bashar al-Assad. The low-intensity conflict on Israel’s northern border is designed to remind Tel Aviv that it will always have to take account of Hizbullah. The latter has greatly strengthened its military capabilities since the ‘33-day war’ in 2006, which it considers a victory. And although Hizbullah recognises Israel’s air supremacy, its leaders claim they don’t fear a land battle.

A week after the Hamas raids, Iran’s supreme leader Ayatollah Ali Khamenei threatened Israel with military intervention if it continued its air strikes on Gaza. ‘If the crimes [of the Zionist regime] continue, Muslims and the resistance forces will lose their patience and no one will be able to stop them,’ he declared on 17 October. Meanwhile, foreign minister Hossein Amir-Abdollahian has warned the US and Israel that the situation in the Middle East could ‘get out of control’ – in other words Iran won’t be able to stop Hizbullah and its allies from attacking Israel.

On 19 October a US warship in the Red Sea intercepted several missiles and drones launched by pro-Iranian Houthi militia in Yemen. These long-range weapons were headed north and, according to Washington, could have reached Israeli territory. Iranian media close to the regime call daily for armed Shia factions in Lebanon, Yemen, Syria and Iraq to unite against Israel. There is now a serious risk of wider conflict in the region.

Conscious of the dangers of a second front, Israel has evacuated a number of communities close to the border and issued more warnings to Hizbullah and Iran. Border skirmishes have intensified and become more frequent, as in the lead-up to the 2006 war. But is it really in Hizbullah’s interest to start a war? That would risk a riposte from Washington. Forty years ago, US warships bombarded the Lebanese coast in response to two truck bombings in Beirut that killed 241 US service members and 58 French paratroopers. The Hamas attack has seen a return in force of the US Navy, as phase two of Israel’s retaliation plays out in Gaza.