An Unjust War

There are very good grounds for saying that the joint attack on Iran by the United States and Israel was reckless, illegal and immoral. The only possible justification – that if successful, it would make the world a better place – depends on a chain of possibilities that are highly implausible.

From the Editor, The Tablet, 4 March 2026

Donald Trump insists he is coming to the aid of opponents of Iran’s brutal theocratic regime, who should, he says, rise up and seize power now the country’s leadership has been decimated by military action. But a new leadership is already in place, seemingly identical in its ideology to its predecessor, and no more inclined to be merciful to any protesters who dare to take to the streets. They will be massacred again.

The regime’s opponents, mostly living in exile, are ill-organised and divided, with apparently no significant power base in the country. To leave the successful outcome of this enterprise in such hands – and to offer that as its justification – is indeed reckless. Yet apart from this, there is nothing but a vacuum in the Trump administration’s thinking about what it wants to happen next. That suggests it would be satisfied with what Israel itself would be satisfied with – a beaten, humbled and ruined Iran, no longer able to threaten anyone.

Israel has no more interest in the welfare of Iran’s citizens than it has towards the well-being of those in Gaza. The difference is that while, in effect, it controls Gaza, it does not control Iran. Nor does the US.

President Trump’s appeal to Iranian security forces to lay down their arms and surrender, begs the questions – surrender to whom? How? As Sir Keir Starmer put it, in his firm but careful response, the United Kingdom does not believe in “regime change from the skies”: because it would not work and because it would be illegal.

Apart from fanatical supporters of the existing regime, nobody seems to be mourning Ayatollah Ali Khamenei, the supreme leader of Iran, who was killed in a joint Israeli and US air attack on his headquarters. The morality and legality of assassinating an enemy by drones, bombs and rockets, with no pretence of due process and no claim to jurisdiction, is highly problematic. Yet such extra-territorial, extra-jurisdictional executions have become part of the tool kit of modern warfare, certainly since the US “took out” Osama bin Laden, founder of al-Qaida, in Pakistan in 2011. This used to be called murder. It is a general trend away from moral and legal norms in the conduct of international relations, towards the more barbaric doctrine of “might is right”.

In justifying this war against Iran, Israel pleads that it is acting in self-defence, and that is also the US’ argument. The Trump administration has offered various justifications for its actions which are not entirely compatible. It says an Iranian attack was imminent, but by whom, on whom, how and when, has not been explained. The US Secretary of State Marco Rubio said the US knew Israel was about to attack Iran, and acted pre-emptively to forestall any counter-attack on American military bases. This playground logic has no basis in law. Under Article 51 of the UN Charter, self-defence is legitimised in strict and narrow circumstances, such as when an armed attack on a country has already begun. The Charter would allow a threat to be countered by pre-emptive military action when it was imminently and immediately ready to be launched, such as when troops were amassed at the border and about to cross it.

That bears no relation to this case so far as the US was concerned. The US administration has yet to present any evidence that a possible attack from Iran on US assets or allies had been impending when the US and Israel decided to launch a joint military operation against the country. Israel on the other hand could argue that an attack on it from Iran is always imminent, as Iran has sworn to annihilate “the Zionist entity” by any means, and if it succeeded in developing nuclear weapons it would be in a position to do so. But for decades the threat from Iran has been contained, and only a few months ago the White House was insisting that “Iran’s nuclear facilities have been obliterated and suggestions otherwise are fake news”. Israel and Iran have no shared border and are separated from each other by about 1,000 miles. The chances of an attack on Israel from a much-weakened Iran succeeding were close to zero.

So the US and Israel action against Iran was illegal. However Iran’s response, which includes attacks on US bases in the region and civilian and commercial infrastructure in the Gulf states where those bases are positioned, has changed the calculus. Iran may have expected these Gulf states to ask their US allies to back off. Instead they are turning on Iran itself as the aggressor, and are asking for help to defend the lives of British people in the area. It will be forthcoming and it will be lawful. And moral. The criteria for just war will be satisfied. It obviously meets the jus ad bellum criteria, and being restricted to the source of the bombardment the Gulf states are experiencing, such as missile launch sites, it also meets the jus in bello test. The further test, jus post bello, which might be summarised as “You break it, you own it”, and which the US and Israel are manifestly failing, does not apply as there is no intention to destabilise the country.

On the broader issues of just war, such as the legitimacy of pre-emptive strikes, the verdict must also be negative. The tests were well stated by Lord Guthrie and Sir Michael Quinlan in their treatise on just war theory in 2007. “The concept of justified pre-emption still needs to be handled very warily,” they wrote. It may easily slide from genuinely pre-emptive action into a broader and more dubious concept of preventive action. “The tests need to include an honest weighing of whether the action we seek to forestall is in truth highly probable (not merely possible) and imminent, and of a kind and weight that would leave us crucially damaged. The hurdle of justification for pre-emption should continue to be set very high.” The attack by Israel and the United States on Iran did not come close to meeting those conditions.

Trump has expressed his dissatisfaction with Starmer’s refusal to allow the Americans to use British bases to launch this war on Iran. By relying on principled moral and legal objections to the US’ actions, Starmer deserves credit. His political opponents in the Conservative and Reform UK parties, who have declared their unconditional support for American actions, do not. A world that ignores morality and international law would not be a safe place to live.