Israel–Iran War: From Asymmetric Deterrence to Direct Military Confrontation

Summary

Since October 2023, Israel has degraded the Iranian-led axis of resistance. Israel successfully involved the United States in targeting Iran’s nuclear programme, thus avoiding a prolonged conflict that could have revealed Israel’s vulnerabilities on the home front. Iran’s restrained approach to escalation during the war was about containing the scope of the conflict and defeating aggression.

Israel’s surprise attack on Iran on 13 June 2025, targeting its nuclear and missile programmes, along with US strikes on Iran’s nuclear facilities, was the first open military conflict involving the Islamic Republic of Iran since the end of the Iran–Iraq War (1980–1988). Since the end of the Cold War, Iran has pursued an asymmetric deterrence strategy against the United States, which has significantly superior conventional military capabilities and has been the leading force shaping the regional security architecture while isolating and threatening Iran over the nuclear issue.

Over decades, Iran leveraged its ideological narrative of Islamist resistance against US military interventionism and Israel to build a network of allies from Hezbollah in Lebanon to Hamas in Gaza, Shi’i militias in Iraq, and Houthis in Yemen. Iran’s region-wide network of allies afforded Iran the ability to carry out grey-zone attacks against its adversaries, while avoiding full-scale conventional conflict with the US.[i]

During the Iran–Iraq war, Iran’s Islamic Revolutionary Guard Corps (IRGC) was responsible for developing a sophisticated ballistic missile programme, which is at the core of its deterrence by punishment through the credible threat of significant retaliation.[ii] It has used the threat of horizontal escalation for deterrence and crisis management. Iran also supported its non-state allies in developing capabilities for fire-centric warfare against Israel and others in the region.

However, the Israeli Defence Forces (IDF), learning from its experience of the Israel–Lebanon war in 2006 and episodic conflicts with Hamas, revised its force design, tactics and operational objectives to counter Iran’s strategy of indirect deterrence. Since October 2023, Israel has maintained the strategic initiative in degrading the Iranian-led axis of resistance, culminating in a direct attack on Iran. Tehran’s decision not to intervene in defence of its allies in Lebanon and Syria, out of fear of Israeli escalation, illustrated the overreach of Iran’s asymmetric strategy of deterrence and defence.[iii]

Israel’s Counter to Iran’s Asymmetric Deterrence

In 2018, Naftali Bennett, then Education Minister of Israel, emphasised the need to reorganise the IDF’s operational and strategic priorities under the ‘Octopus doctrine’. He used the metaphor to explain Iran’s strategy of indirect deterrence through its regional network of allies, as he called on Israel “to aim at the head of the octopus and not its tentacles”. Israel was encouraged by US President Donald Trump’s unilateral withdrawal from the multilateral nuclear agreement with Iran in 2018 and Washington’s sanctions-based ‘maximum pressure’ campaign on Iran, including designating the IRGC as a Foreign Terrorist Organisation.

To prevent the IRGC from establishing a permanent military presence in Syria near Israel’s northern borders, Israeli national security officials devised ‘mabam’ or ‘the campaign between the wars’.[iv] This was a carefully calibrated campaign that leveraged high-quality intelligence to strike high-value targets, including Iranian weapons and rocket depots, Iran’s command headquarters, and intelligence and logistics sites around Damascus. In 2018 alone, Israel dropped about 2,000 bombs on Iranian targets in Syria. The idea was that precision targeting and the lack of public acknowledgement of these actions by Israel would lead Iran to absorb the losses and ultimately discourage it from establishing the more permanent presence it sought. During Bennett’s brief tenure as Defence Minister, the IDF also established the Strategy and Third Circle Directorate, aimed at evaluating threats from Iran reaching Israel’s borders through a unified lens and providing operational recommendations.

After Iran responded to the US withdrawal from the nuclear agreement by reversing restrictions on its nuclear programme, Israel escalated covert operations targeting Iran’s nuclear facilities, including the assassination of the chief Iranian nuclear scientist, Mohsen Fakhrizadeh, in November 2020. Israel’s longstanding opposition to Iran’s nuclear programme is rooted in its potential role as a deterrent, serving as a shield against any Israeli direct hostile actions. At the same time, Iran threatens Israel through its network of allies on Israel’s borders.

Under the multi-year Momentum plan, the IDF revised its force build-up and operational concept of victory to address the missile-centric challenge from Iran and its allies.[v] The goal was to regain a qualitative edge over the enemy by leveraging new sensor technology, artificial intelligence and machine learning to create a more lethal and precise force. Momentum’s force build-up programme incorporated stand-off fire and ground manoeuvring approaches to warfighting. It involved establishing a multi-domain ground manoeuvre capability, meaning that field units would operate simultaneously on land, underground, in the air, in the electromagnetic spectrum, and in the cyber domain, to close the sensor-to-shooter cycle within seconds.

Secondly, it included upgrading Israeli firepower strike capabilities, including long-range strikes on Iran. The third focus was strengthening defences for the Israeli home front through a multi-layered air and missile system designed to intercept threats that persisted despite the offensive actions. The primary definition of victory was revised from focusing on seizing territory to the rapid and systematic destruction of enemy fighting capabilities.

Since October 2023, when Israel responded to Hamas’ attack on Israel by launching a war aimed at eliminating Hamas’ leadership and military capabilities, it has maintained the strategic initiative in escalating the conflict across the Iranian-led ‘axis of resistance’. As Israel utilised its superior intelligence capabilities and air power to degrade Hezbollah’s leadership and military capabilities and targeted IRGC commanders in Lebanon and Syria, Iran was pushed into a reactive posture.

After the Israeli attack on Iran’s Beirut consulate in April 2024, Iran used ballistic missile strikes to establish deterrence by punishment. Iran’s targeting of the IDF’s Nevatim air base and an intelligence centre was the first state-on-state attack aimed at demonstrating Iran’s capabilities and willingness to escalate against a conventionally superior and nuclear-armed adversary.[vi] However, Iran’s measured missile and drone strikes—repeated in October 2024 after Israel assassinated Hezbollah leader Hassan Nasrallah and the top IRGC commander in Syria—exposed Iran’s dilemma of trying to restore deterrence while controlling escalation to prevent full-scale war.

Israel responded to Iranian counterattacks with long-range precision strikes on the S-300 system’s target engagement radar deployed in central Iran.[vii] The subsequent strike in October 2024 aimed to hinder Iran’s production of long-range ballistic missiles by targeting solid fuel mixing equipment. Iran, therefore, failed to deter Israel, which had become committed to a long-term campaign of degrading all components of the Iranian-led axis and weakening Iran itself. Additionally, Iran’s retaliation was limited by US warnings against escalation. At the same time, Israeli defences benefitted from cooperation with the US and Western allies, who also provided diplomatic cover for Israeli military actions. Israel also successfully enlisted the United States in carrying out attacks on Iran’s nuclear facilities. As the US became directly involved in an offensive against Iran, it marked the era of controlled escalation involving Iran and the US.

Escalation Dynamics during the War

Israel’s surprise attack on Iran’s nuclear and missile sites on 13 June came at a time when Washington and Tehran had been engaged in negotiations on the nuclear issue. Israel’s air attack and use of intelligence infiltration inside Iran to carry out targeted assassinations of top military command and suppression of air defences were aimed at disrupting the IRGC’s functioning as a system and making it difficult for Iran to retaliate. Israeli Prime Minister Benjamin Netanyahu declared that the objectives of the military operation, dubbed ‘Rising Lion’, were to eliminate the double existential threat posed by Iran’s nuclear programme and its ballistic missile capabilities.

Given that the International Atomic Energy Agency (IAEA) has stated it found no evidence of a systematic effort by Iran to develop nuclear weapons, Israel’s framing of the attack on nuclear facilities as ‘pre-emptive strikes’—implying an imminent threat—was intended to rally support from its Western allies. Netanyahu’s statement that he ordered plans for the attack in November 2024, shortly after the killing of Hezbollah leader Hassan Nasrallah, suggests that Israel was motivated by the strategic opportunity created by the weakening of Iran’s allies and the degradation of Iran’s air defences in previous Israeli strikes.

In a video statement announcing the operation, Netanyahu made a direct appeal to the Iranian people: “This is your opportunity to stand up.”[viii] The attacks on residential areas, the intimidation of the population through repeated evacuation orders, and propaganda designed to exploit divisions within Iranian society indicated that Israel’s goal was to seek the collapse of the Islamic Republic.[ix] The long-term Israeli objective remains to erode Iran’s nuclear and military capabilities.

Despite the initial shock, Iran restored its military command and opted for a measured, non-escalatory response against Israel. Iran’s smaller missile salvos also suggest that it was preparing for an attrition strategy. After Israel targeted the South Pars gas field on 14 June, Iran launched strikes against the Haifa refinery on the same day.[x] In response to attacks on Iran’s nuclear research centres, it targeted the Weizmann Institute of Science. To some extent, Iran’s demonstration of its ability to deliver a symmetrical response was geared towards controlling escalation. Iran also engaged in counter-value targeting in major Israeli cities to increase the costs imposed by its missile strikes.

However, the United States entered the conflict with escalation dominance over Iran. Its approach of limited, calculated strikes against Iran’s nuclear facilities, followed by overtures for de-escalation, led Iran to respond with a largely symbolic action. Although Iran had long declared that an attack on its nuclear sites would prompt an escalatory response, such as closing the Strait of Hormuz or attacking US bases in the Persian Gulf States, Tehran’s restraint in responding was dictated by the fear of an overwhelming retaliation by the US and the imperative of state survival. This was especially true given President Trump’s deliberate ambiguity about US objectives, whether limited to targeting nuclear sites or potentially seeking regime change. Nevertheless, by retaliating with a missile strike on the US Central Command forward base at Al Udeid in Qatar, Tehran signalled that it is willing to expand the scope of the conflict to the Gulf States in response to US escalation against Iran.

Israel conducted its operation against Iran with limited goals and in a compressed timeframe. It successfully involved the United States in targeting Iran’s nuclear programme, thus avoiding a prolonged conflict that could have further exposed Israel’s vulnerabilities on the home front. Iran’s restrained approach to escalation during the war was about containing the scope of the conflict and defeating aggression rather than seeking to dominate through offensive responses.[xi] To confront a long-term Israeli campaign aimed at dismantling Iran’s military capabilities and seeking the collapse of the Islamic Republic, Iran will likely employ an entrenched defence strategy of increasing resilience of its forces, especially rebuilding its air defences and counter-intelligence capabilities. Iran will potentially have to contend with Israel’s ‘campaign between wars’, sabotaging Iranian efforts to rebuild its air defences and missile capabilities, including support for separatist outfits in Iran’s geographical periphery.

Tehran will redouble its diplomatic dialogue on regional peace and security with Persian Gulf neighbours.[xii] Tehran has also shown openness to a regional-led solution to the contentious issue of uranium enrichment on Iranian soil, which led to a stalemate in US–Iran indirect talks.  Reviving diplomacy with European signatories of the JCPOA will be crucial to prevent them from using the so-called snap-back of sanctions on Iran. The reformist government of Massoud Pezeshkian, despite dissenting voices among hardliners, has also sought to revive diplomacy with Europe and potentially with Washington to keep it from green-lighting further Israeli attacks.

Views expressed are of the author and do not necessarily reflect the views of the Manohar Parrikar IDSA or of the Government of India.

[i] Dana Stroul, “How Iran Could Escalate: Tehran’s Bad Options—and Washington’s Best Response”, Foreign Affairs, 23 June 2025.

[ii] Hamidreza Azizi, “The Concept of ‘Forward Defence’: How Has the Syrian Crisis Shaped the Evolution of Iran’s Military Strategy?”, Geneva Centre for Security Policy, February 2021.

[iii] Deepika Saraswat, “Iran’s Strategic Recalibration Amid Geopolitical Shifts in West Asia”, Issue Brief, Manohar Parrikar Institute for Defence Studies and Analyses (MP-IDSA), 27 December 2024.

[iv] Ilan Goldenberg et al., “Countering Iran in the Gray Zone: What the United States Should Learn from Israel’s Operations in Syria”, Centre for New American Century, 1 April 2020.

[v] Yaakov Lappin, “The IDF’s Momentum Plan Aims to Create a New Type of War Machine”, BESA, 22 March 2020.

[vi] “23 Missiles Reportedly Hit Nevatim and Tel Nof Military Bases During Iran Attack”, The Times of Israel, 4 October 2024.

[vii] Alexander Palmer et al., “Assessing Israel’s Strike on Iran”, Centre for Strategic and International Studies, 3 May 2024.

[viii] Jacob Magid, “Netanyahu to Iranian People: We Hope Our Operation Will Clear Path to Your Freedom”, The Times of Israel, 14 June 2025.

[ix] “Explosions Reported in Tehran After Israeli Evacuation Order”, The Times of Israel, 20 June 2025.

[x] “Iranian and Israeli Energy Sites Impacted by Conflict”, Reuters, 17 June 2025.

[xi] Jim Lamson, New Missiles, “New Risks: The Escalatory Implications of Iran’s Precision-Strike Weapons”, War on the Rocks, 14 January 2022.

[xii] Javad Zarif, “Build Regional Stability from the Ashes of Netanyahu’s War on JCPOA”, Al Jazeera, 15 July 2025.