Vladimir Putin, of all people, along with several European leaders, has declared that “the US- Israel war against Iran is illegal under international law.” So does Israel’s military action in Iran, with all its ramifications, meet the test of international law? After the past two and a half years, and the relentless mistreatment of Israel by international bodies, many may find the question beside the point. But it still matters.

The short answer is yes. Throughout this difficult period, Israel has acted in accordance with international law, and it is doing so now. The fundamental rule of customary international law – also reflected in Article 2(4) of the UN Charter – prohibits the use of force. The exception to this rule, and the basis for any state’s legitimate use of force, is the right of self-defense (Article 51 of the UN Charter). That right arises when a state is subjected to an “armed attack.”

As we all know, Iran has been acting against Israel for many years. It deploys Hezbollah and the Houthis against us, and Hamas has effectively been armed and enabled by Iran. Since these forces are subordinate to Iran and operate under its direction, that in itself amounts to an Iranian armed attack on Israel.

But Iran has also attacked Israel directly, without Israel attacking Iran first. In April 2024, Iran fired hundreds of missiles and drones at Israel, and it attacked Israel again in October 2024. These direct attacks establish, in the clearest possible way, Israel’s right to self-defense.

Israel also relies on the doctrine of “Preventive Self-Defense.” This is a broader reading of Article 51, grounded in customary international law and the 19th-century Caroline Formula, which holds that a state may strike first when the need for self-defense is “immediate, overwhelming, and leaves no choice of means or time for deliberation.” The Israel-Iran case plainly fits that description.

Iran has poured enormous resources into building the capacity to destroy Israel. It has developed a vast missile arsenal and pursued nuclear weapons while repeatedly declaring that these are meant to eliminate Israel. In the heart of Tehran, it set a clock counting down to Israel’s end. This is an immediate threat that Israel has both a duty and a legal right to eliminate.

Another way to justify the legal basis of the action is to recognize the reality of recent years as an ongoing state of war between Israel and Iran. If so, the current “Roaring Lion” campaign and last June’s “Rising Lion” operation are simply rounds in a continuing conflict – rather than separate wars each requiring a fresh, standalone justification.

To be sure, many international-law experts reject these arguments. From a narrow, literal reading of the UN Charter, they contend that past actions cannot be treated as an “armed attack” justifying a response today; and that even the gravest future threat cannot justify a preemptive strike. Israel’s critics will also argue that using force without Security Council authorization is an “act of aggression.”

By clinging to the Charter’s text, these positions deny Israel the ability to defend itself. October 7 taught us that cutting off the capacity to destroy the State of Israel, when an enemy openly declares that as its intent, is not optional. It is vital. And when it comes to Iran, the bitter truth is that international institutions have failed. Political vetoes and conflicting great-power interests have long paralyzed them. When the multilateral system cannot enforce even its own decisions on nuclear proliferation or state support for terror, responsibility and authority return to their natural source: the sovereign state charged with protecting its citizens.

International law is meant to safeguard peace and the value of human life. It was never meant to function as a collective suicide pact for the State of Israel, or for the West. Israel abides by international law; its enemies cynically weaponize it against Israel. Under conditions of a concrete, existential threat, striking Iran is not an assault on the world order – it is an effort to restore the most basic logic that order is supposed to embody.

This is the struggle for Israel’s right to exist in the most fundamental sense. A right that no international norm can negate.

© The Times of Israel (Blogs)