The entrenched rivalry between Israel and Iran has evolved into one of the most volatile fault lines in the Middle Eastern geopolitics. At its core lies the mutual invocation of existential threat, an emotionally charged narrative that both states deploy to justify military aggression and nuclear politics. This study interrogates the Israel-Iran nuclear armament contestations through the lens of Nuclear Deterrence Theory by Bernard Brodie (1946). Adopting a qualitative research design and employing a secondary method of data collection, the study draws from scholarly works, policy documents, intelligence reports, official statements, and reports of reputable media sources. Through content analysis, it critically examines how both Israel and Iran construct and deploy narratives of existential threat to justify their nuclear postures, while revealing how these discourses intersect with asymmetries embedded in the global non-proliferation regime. The findings reveal that the Israel-Iran nuclear impasse transcends a conventional security dilemma, reflecting a structurally biased international nuclear order. Israel’s opaque nuclear arsenal, shielded by U.S. patronage and exempted from non-proliferation scrutiny, starkly contrasts with Iran’s treaty-bound yet disproportionately sanctioned nuclear activities. This asymmetry fosters an environment where nuclear deterrence is monopolised rather than reciprocal, fuelling regional instability and incentivising nuclear latency. The study concludes that existential threat narratives, strategically invoked by both states, entrench distrust and securitisation, inhibiting meaningful diplomatic engagement. Consequently, the study recommended among others for the establishment of a universal accountability mechanism under a reformed IAEA or UN-based framework to address enforcement disparities.

Key words: Israel, Iran, nuclear deterrence, existential threat, non-proliferation