The pressures for an inquiry into the war in Iraq will not disappear just because the law lords have rejected a call for one made on behalf of two mothers whose sons died there.

Yesterday’s judgment, rarely by all nine law lords, turned on whether the Human Rights Act, and Article 2 of the European Convention on Human Rights, could require the holding of an independent public inquiry into the invasion. This is not about whether such an inquiry is desirable in the public interest, or whether the use of armed force was lawful in international law. The case is a much narrower one about whether the duty in Article 2 on protecting life means that a state should take reliable legal advice before military action.

All nine judges were unanimous that this right could not be established, not least because the lawfulness of military action has no immediate bearing on the risk of fatalities. An unlawful surprise attack could minimise the risk of casualties. Lord Bingham of Cornhill, the senior law lord, added that the courts had traditionally shown restraint on “what has been called high policy – peace and war, the making of treaties and the conduct of foreign relations”.

Baroness Hale of Richmond said the legal advice by Lord Goldsmith, QC, then the Attorney-General, on March 7, 2003, was “very far from clear and unambiguous”, though, within ten days, this had been firmed up to provide the authority to use force. She said: “If my child had died in this way . . . I would want to feel that she had died fighting for a just cause, that she had not been sent to fight a battle which should never have been fought at all, and that if she had, then someone might be called to account.” She wished that a duty could be spelt out for states not to send soliders to fight in an unlawful war, but doubted that this would happen.

The legal issue, however, is only one aspect of the call for an inquiry, renewed yesterday by both the Conservatives and the Liberal Democrats. Indeed, I doubt if much new would emerge either on the legal or the intelligence background (fully covered in the report by Lord Butler of Brockwell in 2004).

Far more important than the why is the how: what Sir Jeremy Greenstock, the former British Ambassador to the United Nations and envoy to Baghdad in 2003, described as the “woefully inadequate planning” for the aftermath of the invasion. The Government is resisting an inquiry not just because British troops are still in Iraq but, as William Hague and Michael Howard argued in the Commons a fortnight ago, because it could be embarassing before a general election.

Any comprehensive inquiry would expose the fraught relations between London and Washington, and on the ground between British and American commanders and diplomats, about operations in Iraq after the capture of Baghdad five years ago. Any investigation now that had full access to private conversations and logs, which it should, would be bound to be very damaging for British-American relations. That could have an impact on operations in Afghanistan and would make talk of the “special relationship” sound very hollow.

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