Why is there war with Iran?

Saturday 28 February 2026

The long confrontation between Israel, the United States and Iran has often been described as a shadow war — fought through proxies, cyber operations, covert strikes and economic sanctions. Yet in recent years it has come perilously close to open regional conflict. To understand why Israel and the United States have come to view Iran’s nuclear and ballistic missile programmes as sufficiently grave to justify starting a major war today, one must place contemporary developments within a longer historical and strategic arc.

The origins of the crisis lie not in the present decade but in the revolutionary rupture of 1979.

The 1979 Break: Ideology and Existential Threat

The overthrow of the Shah and the establishment of the Islamic Republic under Ruhollah Khomeini transformed Iran from a pro-Western monarchy into a revolutionary theocracy committed, in principle, to resisting American influence and opposing Israel’s existence. The seizure of the United States embassy in Tehran and the 444-day hostage crisis crystallised American hostility. For Israel the ideological shift was even more acute: the Islamic Republic openly adopted a rhetoric that questioned Israel’s legitimacy as a state.

For the first decade after the revolution Iran’s focus was survival — most notably during the devastating Iran-Iraq War. Yet that war also planted the seeds of Iran’s missile doctrine. Facing Iraqi missile attacks on her cities, Iran concluded that ballistic missiles were essential instruments of deterrence. Over time she developed a sophisticated missile programme capable of striking across the Middle East.

This doctrinal lesson — that strategic depth could be achieved through missiles and proxies — became central to Iranian military planning.

The Nuclear Question Emerges

Iran’s nuclear ambitions predate the revolution, but it was the post-2002 revelations of clandestine enrichment facilities at Natanz and Fordow that alarmed the international community. Western intelligence assessments concluded that Iran had mastered significant elements of the fuel cycle — including uranium enrichment — that, while civilian in declared purpose, could be diverted to weapons-grade material.

For Israel the calculus was stark. Unlike the United States she lacks strategic depth. A single nuclear weapon detonated over Tel Aviv or Haifa would be existential in effect. Israel’s military doctrine has therefore long included preventive action against hostile nuclear programmes — most famously the 1981 strike on Iraq’s Osirak reactor.

Iran however, is not Iraq. Her facilities are dispersed, hardened and often buried deep underground. Preventive strikes, like the ones undertaken by the United States in June 2025, are complex and potentially regionally destabilising. Hence, the Israeli concern gradually shifted from stopping a reactor to preventing an entire technological infrastructure from crossing the threshold to weapons.

The United States shared these concerns but approached them differently. Washington sought containment through diplomacy and sanctions. This culminated in the 2015 Joint Comprehensive Plan of Action, negotiated under Barack Obama, which limited Iranian enrichment levels and subjected facilities to international inspection.

Collapse of the Nuclear Agreement

The withdrawal of the United States from the agreement in 2018 under Donald Trump and the re-imposition of sanctions marked a turning point. Iran responded incrementally by exceeding enrichment caps and deploying more advanced centrifuges. Enrichment levels rose to 60 per cent purity — technically below weapons grade but far beyond civilian necessity.

From Israel’s perspective, the problem ceased to be theoretical. The “breakout time” — the period required to produce enough fissile material for a bomb — shortened dramatically. Even if Iran had not decided to build a weapon, she was approaching the capability to do so quickly and covertly.

This distinction between capability and intent is central. Israel’s security doctrine assumes that hostile intent can crystallise rapidly — especially in volatile political environments. Therefore capability itself becomes unacceptable.

For the United States, the matter was entwined with broader regional commitments. American forces are stationed across the Gulf. A nuclear-armed Iran could shield her conventional and proxy activities under a nuclear umbrella, emboldening groups such as Hezbollah in Lebanon or militias in Iraq and Syria.

The Missile Dimension

If nuclear capability represents strategic deterrence, ballistic missiles represent delivery. Iran has invested heavily in medium-range systems such as the Shahab and Sejjil series, capable of reaching Israel. She has also refined precision-guided munitions distributed to allied groups.

For Israel, this combination — enriched uranium approaching weapons grade and missiles capable of reliable delivery — evokes a narrowing window. Even absent a completed warhead, missile salvos from Iran or her proxies can saturate defences and impose sustained attrition. The 2006 war with Hezbollah demonstrated the disruptive potential of even relatively unsophisticated rockets.

Moreover, missile technology is far less constrained by international agreements than nuclear material. The technological base for solid-fuel propulsion, guidance systems and mobile launch platforms continues to mature. Once mastered, it cannot easily be dismantled.

Strategic Psychology and the Question of Timing

Why now?

Several converging factors sharpen perceptions of urgency.

First, regional alignment has shifted. The Abraham Accords have drawn some Arab states closer to Israel. Iran perceives encirclement; Israel perceives opportunity.

Secondly, American domestic politics have oscillated between engagement and maximum pressure. Uncertainty regarding long-term United States commitment has encouraged Israel to contemplate autonomous action.

Thirdly, technological thresholds have been crossed. The accumulation of highly enriched uranium — combined with advanced centrifuge deployment — reduces warning time. Intelligence services may judge that the margin for preventive action is shrinking.

Finally, war itself has become normalised across the region. Syria’s protracted conflict, the struggle against Islamic State and the intermittent Gaza wars have habituated regional actors to persistent instability. The psychological barrier to escalation is lower than it once was.

Existential Doctrine versus Strategic Patience

Israel’s doctrine has always been shaped by vulnerability. She has neither the territorial depth of the United States nor the demographic scale of Iran. Her security philosophy emphasises deterrence, rapid mobilisation and, when necessary, pre-emption.

The United States, by contrast, weighs global consequences. A major Middle Eastern war risks oil market disruption, alliance strain and confrontation with other powers. Yet Washington also calculates that a nuclear-armed Iran could trigger proliferation across Saudi Arabia, Turkey and Egypt, fundamentally destabilising the non-proliferation regime.

Thus the convergence of Israeli existential anxiety and American non-proliferation strategy produces a moment in which preventive war appears, to some policymakers, less dangerous than strategic acquiescence.

War as a Decision of Perception

Whether a major Middle Eastern war is inevitable remains uncertain at the time of writing. Iran insists her nuclear programme is peaceful. Israel insists that rhetoric combined with capability cannot be trusted. The United States stands between deterrence and diplomacy. The United States has started striking Iran and Iran has started assaults on Israel and US military bases across the Middle East.

History suggests that wars over emerging technologies are often wars of anticipation — conflicts fought not over what exists, but over what might soon exist. In the case of Iran’s nuclear and ballistic missile programmes, it is the compression of time — the shortening distance between enrichment capability and deliverable weapon — that has transformed a shadow war into open conflict so quickly.

The tragedy is that once preventive logic takes hold, diplomacy becomes hostage to physics. Centrifuges spin; missiles test; intelligence windows narrow. And in such an atmosphere, fear itself can become the most decisive weapon of all.