Israel did not immediately say where or how the strikes were being carried out.

During an earlier exchange of airstrikes in April, Israel waited only about five days to respond to an Iranian attack similar to Tehran’s October 1 attack.

But various factors seem to have dictated a longer lead-up to a response this time, including talks between Israel and the Biden administration, the arrival of a United States air defence system and the Jewish holidays. The coming US election could have also affected Israel’s timing.

How have Israel and Iran arrived at this point?

For decades, Iran and Israel engaged in what amounted to a shadow war. Iran has used a network of allied groups, including Hamas and Hezbollah, to attack Israeli interests, and Israel has assassinated senior Iranian officials and nuclear scientists and staged cyberattacks against Iran. The conflict between them burst into the open this year, in the aftermath of the October 7, 2023, attacks by Hamas on Israel.

In April, Iran launched a barrage of missiles and drones at Israel – its first direct attack on the country – in retaliation for an Israeli strike on an Iranian Embassy compound in Syria’s capital, Damascus, that killed three top Iranian commanders. Israel largely thwarted the Iranian missile barrage using its air defences, assisted by the US and other allies, and then responded with an attack of its own.

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Then, in late July, Israeli jets killed a top commander of Hezbollah in Lebanon’s capital, Beirut, in retaliation for a rocket attack that killed at least 12 people. One day later, Hamas’ political leader, Ismail Haniyeh, was killed in an explosion in Tehran.

The Iranian government and Hezbollah vowed to retaliate, but, to the surprise of many, Iran took no immediate action.

It launched a missile barrage at Israel on October 1, which Iran’s Revolutionary Guard said was in retaliation for the assassinations of Haniyeh; Hezbollah’s leader, Hassan Nasrallah, late last month; and an Iranian commander.

What were Israel’s potential targets?

After severely weakening Iranian-backed Hezbollah and Hamas, Israel was trying to balance its strategic goals with concerns from its allies, particularly the US, that a new attack could set off a wider regional war.

The Israeli government had told the Biden administration that it would avoid striking Iran’s nuclear enrichment and oil production sites, two officials said earlier this month. The officials, who spoke on the condition of anonymity to discuss sensitive diplomacy, said Israel had agreed to focus its attack on military targets in Iran.

As of early Saturday in Iran, it was unclear what targets Israel did or did not strike.

Avoiding nuclear or oil infrastructure sites may reduce the likelihood of an all-out war between the two adversaries, which would be devastating for the region. It also raised US concerns about being dragged into a bigger Middle East confrontation with the presidential election less than two weeks away.

What are Israel’s military capabilities?

Israel has recently shown that it is capable of carrying out airstrikes over long distances.

In assaults against the Houthis in Yemen at the end of September, Israeli forces flew more than 1600 kilometres to attack power plants and shipping infrastructure, using reconnaissance aircraft and dozens of fighter jets that had to be refuelled mid-flight. An aerial attack on Tehran, about 1600 kilometres from Israel, would require a similar range.

Iran has much stronger air defences than Lebanon and Yemen, but Israel has shown that it may have an edge.

In April, in retaliation for Iran’s first missile barrage, an Israeli airstrike damaged an S-300 anti-aircraft system near Natanz, a city in central Iran critical to the country’s nuclear weapons program. Western and Iranian officials said Israel had deployed aerial drones and at least one missile fired from a warplane in that attack.

That strike showed that Israel could bypass Iran’s defensive systems and paralyse them.

According to the Centre for Strategic and International Studies, a Washington research institution, Israel has additional options: Jericho 2 medium-range ballistic missiles, which can reach targets about 3200 kilometres away, and Jericho 3 intermediate-range ballistic missiles, which can reach targets more than 6400 kilometres away.

What is the US government’s stance?

President Joe Biden said this month that he would not support an attack on Iran’s nuclear sites.

Asked last week whether he knew when Israel would strike and what kind of targets it had chosen, Biden said yes, but he gave no details. His response implied that the US and Israel might have reached an agreement on the matter. US Secretary of State Antony Blinken held a lengthy meeting with Israeli Prime Minister Benjamin Netanyahu on Tuesday.

This article originally appeared in The New York Times.

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