IRAN-ISRAEL ‘THRESHOLD WAR’ …HAS REWRITTEN NUCLEAR ESCALATION RULES

Israel’s conflict with Iran represents far more than another Middle Eastern crisis – it marks the emergence of a dangerous new chapter in nuclear rivalries that has the potential to reshape global proliferation risks for decades to come.

What began with Israeli strikes on Iranian nuclear facilities and other targets on June 13, 2025 has now spiraled into the world’s first full-scale example of what I as an expert in nuclear security call a “threshold war” – a new and terrifying form of conflict where a nuclear weapons power seeks to use force to prevent an enemy on the verge of nuclearization from making that jump. As missiles continue to rain down on both Tehran and Tel Aviv – with hundreds dead in Iran and at least 24 killed in Israel – the international community is witnessing the collapse of traditional deterrence frameworks in real time.

Unlike traditional nuclear rivalries where both sides possess declared arsenals – like India and Pakistan, who despite their tensions operate under mutual deterrence – this new threshold dynamic creates an inherently unstable escalation spiral. Iran increasingly believes it cannot deter Israeli aggression without nuclear weapons, yet every step toward acquiring them invites more aggressive Israeli strikes. Israel, for its part, cannot permanently eliminate Iran’s nuclear knowledge through military means – it can only delay it through means that would seemingly guarantee future Iranian determination to acquire the ultimate deterrent.

Under this dynamic, neither side can step back without accepting an intolerable outcome: for Israel, an Iran more determined than even in becoming a nuclear weapons nation capable of deterring Israeli action and ending its regional military dominance; for Iran, the risk of regime change through devastating Israeli strikes. The consequences of this deadly logic extend far beyond the Middle East.

The preventive strike precedent

The stakes could not be higher, as Iranian officials have called the attack “a declaration of war” and vowed that destroyed nuclear facilities “would be rebuilt.” Israel, meanwhile has warned its campaign will continue “for as many days as it takes.”

Most ominously, the scheduled nuclear talks between the U.S. and Iran were called off, with Tehran dismissing any such dialogue as “meaningless.” This may suggest diplomacy’s window – which opened for just a few months under Trump’s second administration, after being closed during his first – was deliberately slammed shut.

From strikes to regional conflagration

Israel’s initial strike quickly triggered inevitable escalation. Iran’s retaliation came in waves: first hundreds of drones and missiles on June 13, then sustained barrages throughout the following days. By the morning of June 15, both countries were trading strikes on energy infrastructure, military bases and civilian areas, with no immediate end in sight.

The Houthis in Yemen have since joined the fight, by launching ballistic missiles at Tel Aviv. Notably absent are Hezbollah, Hamas and Iran’s Iraqi militias – all significantly damaged by recent action by Israel. This degradation of Iran’s “axis of resistance” – its traditional forward deterrent – fundamentally alters Tehran’s strategic calculations. Without strong proxies to threaten retaliation, Iran is more exposed to Israeli strikes, making nuclear weapons seem like the only reliable deterrent against future attacks.

The commitment trap

This creates what strategists call the “commitment trap” – a dynamic where both sides face escalating costs but cannot back down. Israel faces its own strategic dilemma. The strikes may ultimately accelerate rather than prevent Iranian nuclearization, yet backing down would mean accepting a nuclear Iran. Netanyahu’s promise that current strikes are “nothing compared to what they will feel in coming days” shows how quickly strikes sold as preventative escalate toward total war.

Unlike established nuclear powers that can negotiate from positions of strength, threshold states, such as Iran, face a stark choice: remain vulnerable to preventive strikes and regime change or race toward the protection that nuclear deterrence provides.

North Korea offers the clearest example of this dynamic. Despite decades of sanctions and military threats, Pyongyang’s nuclear program has made it essentially immune to preventive strikes. Iranian leaders understand this lesson well – the question is whether they can reach the same protected status before suffering decisive preventive action.

Global implication

The international response reveals how thoroughly Israel’s Operation Rising Lion has normalized aggression against nuclear facilities. While European leaders called for “maximum restraint,” none condemned Israel’s initial attacks. Russia and China condemned the attacks but took no concrete action. The U.N. Security Council produced only statements of “concern” about “escalation.”

SOURCE: THE CONVERSATION