The evolution of the use of force in the nuclear age has fundamentally reshaped the logic, legality, and morality of warfare, particularly in conflicts involving nuclear-capable or near-nuclear states. In the nuclear age, the traditional concept of war as an instrument of policy has been constrained by the catastrophic consequences associated with nuclear weapons, giving rise to doctrines such as deterrence, mutually assured destruction (MAD), and anticipatory self-defense. The prohibition on the use of force under Article 2(4) of the United Nations Charter and the exception of self-defense under Article 51 are interpreted and contested in the context of preemptive and preventive military actions against perceived nuclear threats. The US, Israel–Iran war, increasingly described as a “threshold war,” reflects a strategic environment in which force is employed not merely in response to armed attack but to prevent nuclear proliferation and preserve regional power balances. The paper analyzes how the US, Israel-Iran war illustrates the complexities of using force in a nuclearized environment. The paper, which is qualitative and anchored on deterrence theory, argues that while nuclear weapons deter large-scale direct conflict, they simultaneously incentivize limited, covert, and technologically advanced uses of force below the nuclear threshold. This paper found that the nuclear age has not eliminated the use of force but has transformed it into a highly constrained, legally ambiguous, and strategically perilous instrument. The paper recommends the need to strengthen international legal frameworks and renewed diplomatic mechanisms to manage nuclear risks and prevent catastrophic escalation.
Keywords: Use of Force, Nuclear Weapons, Deterrence, Strategy, War
