In a world where nuclear weapons could soon be in the hands of rogue nations like Iran, an Israeli pre-emptive strike on Iran’s nuclear facilities would be fully justified. Despite its ban on aggressive war, Article 51 of the United Nations Charter clearly recognizes a state’s inherent right of self-defense. Thus, Israel has full authority to act unilaterally or collectively in its self-defense.
Yet Article 51 does not create the right to self-defense; it is an inherent right of all states under international law. Hence, determining when self-defense is appropriate lies, as it always has, with states.
Under the charter, however, the U.N. Security Council is charged with lifting the burden of individual national self-defense and taking appropriate steps to restore peace and security. One must recognize, however, that the muscular Security Council envisioned in the charter never materialized. As such, threatened states are required to make their own decisions and bear their own burdens.
Article 51 allows Israel to use aggressive force against Iran’s nuclear program if an “armed attack” occurs. Its plain language is satisfied when one state has used armed force to attack another state. Under customary international law, a pre-emptive strike is also permitted when an armed attack is imminent.
An Israeli attack against Iran’s nuclear facilities would be legitimate for two reasons. First, Iran already is conducting armed attacks under the plain meaning of Article 51 through Islamist terrorist surrogates Hezbollah, Palestinian Islamic Jihad and Hamas, so a de facto state of war exists between Israel and Iran.
Second, even if one questions the notion of proxy attacks, Iran’s development of weapons of mass destruction constitutes an existential threat to Israel.
Under international law, the Article 51 “armed attack” requirement that evokes a right of self-defense can occur when a state perceives that such an attack is “immediately impending and inevitable.” Thus, rather than waiting for an actual attack, a state may execute a pre-emptive strike on the hostile state.
Two elements must be met to legitimize a pre-emptive strike: proportionality and necessity. Necessity is where attention is usually focused. The acting state must have exhausted all other alternatives, and the threat from the hostile state must be imminent. As with most pre-emptive strikes, imminence related to necessity will be the most contested issue in deciding the strike’s legality.
The definition of imminent is when there is “some outward act that initiates the attempt to harm such that the actual harm is close at hand.” Such an attack has been considered imminent when a state could see the mobilization of enemy armed forces. However, according to the modern trend in legal thought, the threatened attack must be perceived as “instant, overwhelming, leaving no choice of means, and no moment for deliberation.” The hostile state must be about to launch an attack and not merely in the “preparatory stages” of an attack.
Yet, even the more “modern” definition has lagged behind the development of technology, particularly of weapons of mass destruction and their rapid delivery. Under the historic definition, Israel would likely be required to wait until nuclear warheads were attached to missiles and about to be launched. But by then, it would be too late. Failure to stop Iran before it reaches this point invites disaster because of the destruction that would occur were such an attack to succeed.
If Israel deems that Iran is preparing for a nuclear attack and failure to act would put it in grave danger, the threat would be imminent. As such, Israel would be justified in making a pre-emptive strike against Iran’s nuclear facilities, as long as the attack were proportional.
While the rule in international law is that a state may not initiate aggressive war toward another state, an Israeli attack on Iranian nuclear facilities would not qualify as aggressive war; it would reflect Israel’s right to self-defense.
Jay Sekulow is chief counsel of the American Center for Law and Justice, based in Washington, D.C. Robert Ash is the group’s senior counsel.