In a region of the world fraught with moral ambiguities there is one thing of which we can be certain: Ayatollah Khamenei, supreme leader of Iran, got what he deserved when he was killed in an American/Israeli air strike on his palace in Tehran.
For nearly 40 years he led a regime which exported terrorism throughout the Middle East, killed tens of thousands of its own people for expressing peaceful dissent and wilfully refused to dispel plausible suspicions that it was seeking a nuclear bomb to obliterate Israel.
But to say that Khamenei, whom President Trump was right for once to call evil, got what was coming to him is not the same as arguing that attacking Iran and killing the old man was the right thing to do. For who knows what comes next? It would have been far better had it been possible to bring him before the International Criminal Court, which would have exposed his crimes to the world while sparing what is, after all, a human life. But that was not practical.
The process of picking a successor as supreme leader has already begun and the chosen one may be even more brutal and murderous, hard though that is to imagine. Or the American/Israeli action may unleash chaos across the region on an even grander scale than that which followed the overthrow of Saddam Hussein in 2003. The situation is developing fast, and at the time of writing there has already been Iranian retaliatory bombing in several countries around the Gulf as well as Israel.
It is the possibility of more regional chaos that is the main worry now. Once again, as in Iraq, the concern is that the Americans do not have clear war aims or a post-war plan.
Benjamin Netanyahu, Israeli Prime Minister, whatever his many grave faults, and even crimes in the eyes of some, at least seems to have a clear purpose in taking his country to war with Iran: quite understandably he wants to stop Iran building a nuclear bomb. As a secondary aim he will want to put a stop to Iranian support for groups like Hamas and Hezbollah. He probably could hardly care less what happens inside Iran afterwards.
President Trump cannot afford to be so insouciant. Without a well thought-out and achieveable plan he fails to meet one of the key tests for fighting a just war which have been applied in the West since Roman times (in theory anyway) and were perhaps most famously set out by the medieval saint and scholar Thomas Aquinas.
Just War theory
Just War theory has evolved with increasing rapidity in recent decades as wars between states have given way to insurgencies and terrorism. The most salient conditions for a just war in the current Iran situation are just cause, last resort, proportionality and reasonable hope of success.
Netanyahu, for all his faults, argues with some justice that depriving Iran of the ability to build a nuclear weapon is a just cause for war for his country and that given the failure of negotiations, this is a last chance to do that. The Israeli Prime Minister, with the assistance of the US and its bunker buster bombs, has reasonable hope of success.
America can argue as its just cause that in depriving Iran of nuclear weapons it is safeguarding not just its ally Israel but the entire Gulf and Middle East. It claims this is a last opportunity to get its enemy to give up its nuclear ambitions, which may be true though its case it weakened by the fact that Iran had a nuclear deal with the West (and Russia and China) which Trump scrapped in his first presidential term.
Whether the war will be waged proportionately from now on remains to be seen. It should be confined to nuclear, ballistic missile and other strategic military sites. Civilian casualties, as always in war, should certainly be avoided by both sides. Further attacks on the non-military leadership should be eschewed.
As to the condition of reasonable hope of success, that depends on whether Trump wants to go further than depriving Iran of nuclear weapons. If he wants regime change, brought about by the Iranian people, as appears to be the case, he may well fail; social breakdown, as happened in Iraq, is a possible alternative outcome.
The real aim of both the US and Israel should be long-term peace and stability for the Middle East as a whole. That will require not just change in Tehran but compromise by the Israelis, not with its own security but in the form of justice for the Palestinians; ultimately these go together. Otherwise this will be another failed, bloody Middle East war.
