Why Israel and Iran had Decided to Avoid a Long War

When the June 2025 war ended, it was the peak of conflict between Israel and Iran. Until 1979, the two states had mutually beneficial relations but following the Islamic revolution this conflict has existed between them. Iran has seen Israel as its nemesis. The Iranian supreme leader Ali Khamenei and many Iranian top officials do not recognise Israel's right to exist.

The conflict has been a top concern for Israel, which has been especially worried about Iran’s nuclear project. Over the years Israel had attempted to slow Iran’s nuclear program before it could produce nuclear weapons, by employing covert tactics such as cyber-attacks and assassination of Iranian nuclear scientists. The Israeli Prime Minister Benjamin Netanyahu and other Israeli leaders have been warning about the threat Iran imposes. It eventually brought this recent confrontation.

Maj. General Eyal Zamir suggested in May 2022 a strategy against Iran. In the June 2025 war, as chief of staff, he led the Israel Defense Forces (IDF) in a confrontation that started with a major Israeli attack. Israel’s spearhead was the Israeli Air Force (IAF) including its air defence, and Israel’s intelligence community. Israel launched two strikes inside Iran in 2024, which were not focused on Iran’s nuclear program but on Iran’s advanced antiaircraft batteries, the S-300, which were neutralised. Then, Israel sought a very short and limited round of confrontations. The June 2025 war was a much bigger campaign.

Iran has allies and proxies across the Middle East, but Hezbollah and Hamas became much weaker after absorbing significant blows in 2024. Those groups were not involved in the more recent confrontation between Israel and Iran. The pro-Iranian groups in Iraq also stayed out of the war. Only the Houthis continued to confront Israel, but in a very limited way. The combination between the decline of Iran’s partners and the weakness of Iran’s air defences gave Israel a rare opportunity to strike. At the same time, Iran was closer than ever to producing nuclear weapons. Israel was concerned that it might be its last chance to stop Iran from having nuclear weapons.

Israel managed to convince its American patron to allow Israel to hit Iran hard. The United States had provided Israel with highly valuable military and political support during the campaign and then, after more than a week of battles between Israel and Iran, the Trump administration bombed three Iranian nuclear sites. The United States had to take into account various constraints, on several levels, like the cost of the war, the need to save munitions for a possible fight with Russia and/or China, and to deal with domestic opposition to the US participating in the war – including inside the Trump administration. No wonder the United States had sought, and quite quickly managed, an end to the confrontation. Israel and Iran also had good reasons to avoid a long war.

Israel’s Constraints

Israel has strong ties with its American patron, but the US – perhaps quite soon – may have pulled back from the June 2025 war. Israel did not want to be left alone during a tough fight with Iran. It required Israel to end the war soon.

Israel always tries to run a short war for several basic reasons, including economic ones. Israel’s economy is trying to recover from the long and highly costly war in Gaza (which costed Israel so far more than $67 billion). The June 2025 war had costed Israel hundreds of millions of dollars a day, and the cost of property damage in Israel was recently estimated at around $1.5 billion. Israel tried to adjust its economy according to the constraints of the confrontation. Yet Israel needed to end the war with Iran soon, or else its economy might have faced a major crisis.

Israelis have grown used to a state of emergency certainly since October 7, 2023, when Hamas and then Hezbollah confronted Israel. Those groups receive aid from Iran so they can fight Israel. The June 2025 war was directly between Israel and Iran. The Israeli public is exhausted after almost two years of war. They would have stood firm as long as the people believed the losses and damage they absorb are worth the outcome of the confrontation with Iran. If Israel had officially insisted its goal is to topple the Iranian regime, it would have been a tall order. The Iranian regime might have been strong enough to survive, and eventually the Israeli public would have therefore felt they are losing, in that sense. The same would have happened if the Israeli public were convinced Israel can quickly defeat Iran.

There are up to 15,000 Jews who live in Iran. They have not been harmed, but during the June 2025 war there was fear among them. If the confrontation had continued – and especially if it had escalated – the situation for Iranian Jews might have got worse. This negative change might not have been initiated by the Iranian regime, because it would have made the regime look bad, but some Iranians might have taken the law into their own hands to assault Jews. Outside the Middle East, as the war would have gone on, there would have been a growing risk that the Iranian regime or its supporters might have attacked Jewish communities.

Israel and the United States could have conducted more air strikes, adding to it raids with special forces and cyber-attacks. Israel also could have continued to assassinate leading Iranian nuclear scientists and top officials. Yet those efforts require a lot of resources and time and there is no guarantee they could have stopped Iran from producing nuclear weapons. Israel, sometimes together with the United States, already tried many of those methods during the last two decades, which only delayed Iran’s nuclear program. Israel could have also tried to assist the Iranian opposition to bring regime change in Iran, which is a complicated task that would too require a long time, and might not succeed. President Trump suggested the possibility of regime change in Iran. However, the United States might hesitate here, following its bitter experience in trying regime change in Iran’s neighbours, Iraq and Afghanistan.

Iran is more than 1,500 km away from Israel. The IAF reaches Iran, but the IAF was built to fight near Israel, not far away. Israel’s fighter-bombers: the F-15, F-16 and F-35 can use drop tanks, but the IAF needs tankers for a long fight. The IAF has a half-century-old Ram (Boeing 707) tanker aircraft that had conduced around 600 aerial refuelling missions during the recent confrontation. Yet since they were too few of those tankers some Israeli aircraft were refuelled by US tankers. Israel seeks to get the new Boeing KC-46 tankers, but before they arrive, the IAF would have struggled to keep a high rate of sorties over Iran in the long run, without significant US assistance. In addition, despite the IAF’s impressive efforts to maintain its aircraft, the IAF must operate following almost two years of fighting, with all its demands on the IAF. Its fighter-bombers are sophisticated and complicated weapon systems, but some of them have been in service for two decades or more, which could make it a challenge to keep them operational if the fight with Iran had been prolonged. Israel had to be careful not to wear down the IAF in a long confrontation with Iran, particularly if in the near future Israel faces a sudden and severe crisis, let alone a war on another front. The IAF would still have been able to fight, but the IAF would have been weaker, which might have made it difficult for the IDF to win at a low cost. Meanwhile, it is possible, if the confrontation with Iran had gone on for months, eventually one or more Israeli aircraft might have been lost. If an Israeli air crew had to abandon its plane because of Iranian anti-aircraft fire, lack of fuel, technical problems or some accident, this crew might have ended up in Iranian hands, which would have been a blow to Israeli morale.

The IAF does not have heavy bombers so there is a limit to how much damage the IAF could inflict. It is another important constraint in a long war. The IAF would also need all kinds of bombs if the fight had gone on. Recently the Director General of the Ministry of Defense, Maj. Gen. (res.) Amir Baram, met with the CEOs of the main defence industries and top officials from the Ministry of Defense. They discussed accelerating the production of key munition needed for a long campaign. Yet there are limits to how many bombs – or the materials to make them – Israel can produce or import. The same is true with the Israeli air defence, which might have ran out of Arrow missiles as the fight had continued. Israel might have had a serious munitions shortage, despite all the US aid in this matter. Although Iran is Israel’s main enemy, the IDF cannot spend too much ammunition in fighting Iran. Some reserve must be saved in case there is a confrontation on another front. After Israel was shocked on October 7, 2023, it must be ready for other nasty surprises that might lead to a war. The United States too has similar considerations, which can delay or reduce the amount of munitions it can deliver to Israel. The US military already has munitions shortage.

The bottom line is strategic, economic and military constraints would have made it hard for Israel to handle a long war, which could have happened, especially if Israel’s goals were not practical.

Iran’s Calculations

Iran has much more territory, population and natural resources than Israel. Israel’s size is around 22,000 km2 and it has 10 million people while Iran’s is more than 1,600,000 km2 and has around 90 million people and enormous natural gas and oil reserves. Israel’s gas reserves are much smaller. Despite all those advantages, Iran would have struggled to run a long fight due to several factors.

Iran could not have been sure if, when, and how much the United States would have continued to strike Iran. President Trump might have assumed Iran is so weak, that he can force it to do what he wants, by continuing to bomb it. Trump also did not forget Iran tried to assassinate him. An ongoing, let alone massive, US offensive against Iran would have changed the power of balance against Iran. Iran had to prevent that by ending the confrontation before it would have been too late for it.

The Iranian regime might have been desperate enough, if the war had gone on, to try to close the Strait of Hormuz, where around 20 million barrels of oil pass per day, which is about 20% of global petroleum liquids consumption. Blocking those straits would seriously disrupt the oil market. The United States could break this siege by force and retaliate against Iran. This fight would have started with the Strait of Hormuz, but it could have expanded into a bigger fight that would have included striking targets all over Iran such as its nuclear sites. Over time, such escalation could have jeopardised the survival of the Iranian regime.

The IAF gained air superiority over Iran’s skies. Iran’s air force is old and cannot match the IAF. The IAF also neutralised a large part of Iran’s air defence. Iran could not have afforded a long war in which Israel can bomb in Iran whenever and whatever it wants. This enormous advantage would have allowed Israel to strike various targets including going after senior officials, up to the supreme leader. This was a huge risk for the regime, that also humiliated it in the eyes of its people, which increased the danger they might topple it.

Iran strikes Israel with drones, but in the last two years the IAF has gained experience in shooting them down, which was evident in the success in this action by the IDF in the June 2025 war. Iran’s main weapon, their surface-to-surface missiles, caused some casualties and damage but Israel began to destroy the launchers. To begin with, Iran had less than 2,000 missiles that could reach Israel and far fewer launchers. Since the IAF had control over the skies of Iran, despite Iran being a huge country, the IAF was able to find and hit those launchers with increasing efficacy. Iran was aware it had to end the war before it was unable to strike Israel with missiles, and by the end of the confrontation Iran was firing far fewer missiles than at the start.

Iran’s economy depends on exporting oil. If Israel had severely crippled Iran’s oil production, Iran could have sold much less oil. For Iran, it was a very good reason to stop the war before this happens. Furthermore, the Iranian economy has been struggling for many years now, not only because of sanctions but also due to corruption, mismanagement and giving priority to foreign adventurers instead of taking care of the Iranian population. Iran has to manage enormous economic challenges such as an energy crisis, while Iran’s currency, the Rial, is at an all-time low. The Iranian regime was aware that if its economy deteriorates even more, due to losing its main income through the difficulty of selling oil, it will increase the probability of an uprising. In recent years there were several waves of demonstrations in Iran. Another outburst might be powerful enough to undermine the Iranian regime. Preventing this requires the Iranian regime to focus on improving its economy by making reforms and removing sanctions, which meant ending the war soon.

If the confrontation had continued, European powers that signed the JCPOA might have suspected that Iran would try, secretly or not, to produce nuclear weapons after or even during the war, to protect itself from attacks. This would have raised the chances that in October, the ‘snapback’ mechanism might be implemented, reinstating UN sanctions against Iran. It was another key economic concern for Iran, adding to the pressure on her to end the war quickly.

Overall, from the perspective of the Iranian regime, they made huge compromises in 1988, ending the war with Iraq, and in 2015, signing the JCPOA, and they have now done another by ending the war – before the cost would have been too high for them.

© Ehud Eilam, 2025, published by RUSI with permission of the authors.

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