Strike first, argue later: The disputed legality of Israel’s Iran offensive

“We will take the initiative and attack the enemy… to assure the security of Israel and the future of the nation.” — Menachem Begin, defending Israel’s 1967 pre-emptive strike on Egypt.

Nearly six decades after Begin’s declaration, Israel has once again invoked that logic to justify its attack on Iran’s nuclear infrastructure. The framing is familiar: existential danger, pre-emptive action, national survival. But today, as in 1967, one fundamental question remains unresolved: was it legal?

Last month, Israel launched a bold and unprecedented air campaign deep inside Iranian territory. Over ten days, Israeli jets struck nuclear facilities, missile infrastructure, and senior military commanders. Israeli officials described the strikes as a “pre-emptive, precise… offensive,” intended to thwart what they called an “imminent existential threat”.

But the operation has sparked fierce debate. Under international law, specifically Article 2(4) of the UN Charter, the use of force against another state is prohibited, except when authorised by the Security Council or exercised in self-defence under Article 51. But what if the threat hasn’t yet materialised? Can a state legally strike first to prevent a future attack? As is often the case in international law, the answer is contested.

Many states in the Middle East, including UAE, Egypt and Saudi Arabia, condemned the strike as an illegal breach of Iranian sovereignty. Meanwhile, Western governments such as the United States, France and Germany cautiously affirmed Israel’s right to self-defence. The UN Security Council convened urgently but remained divided, highlighting the operation’s contested legal status.