Critics of Trump’s Iranian bombing campaign accuse him of violating the international rules-based order. But in all likelihood, the United States is operating within those rules.
One paragraph of one international law governs America’s air strikes, and that is Article 51 of the United Nations Charter.
The Charter is the closest thing the world has to a foundational document, because all UN members signed it.
Although stuffed with vague platitudes and ill-defined aspirations, it is clear enough on some things, including when war is legal. Article 51 declares the “inherent right of individual or collective self-defense if an armed attack occurs against a member of the United Nations.”
America’s UN ambassador Mike Waltz highlighted this on February 28, insisting the bombing was “in line with Article 51 of the Charter.”
He is almost certainly right. Iran has waged an on-off campaign against the US ever since the Islamic Revolution in 1979. Direct attacks by Iranian forces are rare, mostly as retaliation for US attacks on Iran, but Iranian proxies wage a continuing campaign against US forces and shipping.
Supreme Leader Ayatollah Ali Khamenei, killed on the first day of the bombing, spelled out seven years ago that killing American leaders is a key Iranian foreign policy objective: “‘Death to America means death to Trump, John Bolton [National Security Advisor], and Pompeo [Mike, Secretary of State],” he declared. “It means death to American rulers.”
Legally, that is likely all the “just cause” that Washington needs. Critics insist Iran posed no immediate threat to America, with its nuclear weapons and missile programs years from completion.
But, Article 51 says nothing about immediate threats. A single attack is all the justification a state needs to fight back.
If that sounds harsh, blame the UN itself. Back in 1954, keen to keep all members, democracies, and tyrannies in the same camp, the UN Security Council declared there would be no further explanation of what self-defense means in practice. “Neither the Security Council nor the General Assembly has taken a decision which could be construed as a general definition of the scope of the provisions of Article 51.”
In everyday language, this means a state can do anything not specifically forbidden by the Charter. If a state is attacked, there is nothing preventing it from fighting back with full force, and at a time of its choosing.
Hence, Trump is probably within his rights to declare regime change as his objective, just as the Allies were right to declare it in World War II.
Similarly, the laws of war appear to allow the assassination of Khamenei. Anyone in a chain-of-command is a legitimate target, be they army general or supreme leader.
If all this is surprising, it is because in recent years international law has been thought, wrongly, to have a humanitarian hue to it. Some even suggest it is essentially pacifist.
Years ago, when I reported from the United Nations, squadrons of school children would be led through its New York headquarters by guides enthusing on the high ideals of this “community of nations.”
Yet the Charter’s lofty aspirations are just that: rights are implied, not mandated. The hard-rules part of the Charter is confined to order, not justice.
“International Law” is, anyway, a misused concept. There is no agreed body of international law, only a mosaic of conventions and treaties. Some, like the Charter, are agreed by almost all, but many are agreed by only a few, and some of these laws contradict each other.
As Ukraine has found out, a law is, anyway, not much of a law without an enforcement mechanism. Russia’s 2022 full-scale invasion appears to be a clear violation of Article 2 of the UN Charter, prohibiting one country from invading another.
But, the only enforcement mechanism is the UN’s International Court of Justice (ICJ) in The Hague, and the ICJ can only adjudicate if both sides agree to adjudication. Russia has not, so there can be no verdict.
The same is likely if Iran complains about the American attacks. America would refuse ICJ arbitration, meaning a definitive answer to the legality of this bombing campaign will likely never be known.
Chris Stephen is a British foreign correspondent and the author of The Future of War Crimes Justice (Melville House, 2024).
Europe’s Edge is CEPA’s online journal covering critical topics on the foreign policy docket across Europe and North America. All opinions expressed on Europe’s Edge are those of the author alone and may not represent those of the institutions they represent or the Center for European Policy Analysis. CEPA maintains a strict intellectual independence policy across all its projects and publications.
Ukraine 2036
How Today’s Investments Will Shape Tomorrow’s Security
CEPA Forum 2025
Explore CEPA’s flagship event.
