Leading article: The weight of mendacity

There was a dull sense of inevitability as David Cameron announced yesterday the "deeply regrettable" news that Linda Norgrove was not after all killed when one of her captors detonated a suicide vest but probably by an American grenade.

How often have we been here before? The wedding party bombed in July 2008: the US claimed there were no civilian victims, but an Afghan commission revealed that 47 had died; the seven children killed by Task Force 373 in an unprovoked and secret attack in June 2007, their deaths hushed up until revealed by Wikileaks; the three women, two of them pregnant, shot dead in February this year "by militants" it was claimed, until former Independent correspondent Jerome Starkey revealed that they had been killed by Nato forces. The list goes on.

Why this compulsion to mislead? The accumulated weight of mendacity, the insistence that the enemy is evil incarnate and our boys invariably heroic, is merely sickening. The attempt by US forces to rescue Linda Norgrove may or may not have been as urgent as claimed; it is impossible to judge. We cannot doubt that it was difficult and dangerous, and if they had pulled it off we would have been as glad as anyone. But why the need to obscure the truth about how it ended? Why go to such lengths to spell out the alleged cause of Linda's death when the miserable truth was bound to emerge? Why prevail on our Foreign Office to release a statement – "There is nothing at all to suggest that US fire was the cause of death" – which it would be required in short order to eat?

There is growing dismay about the war in Afghanistan on both sides of the Atlantic. It is questionable whether it was ever winnable, but it is becoming clearer by the day that we are not winning it: Hamid Karzai's government is in disarray, beset by corruption scandals and a banking crisis; the Afghan national army shows few signs of developing into a force capable of taking on the Taliban, whose grip on the country tightens by the day. Meanwhile Nato continues to produce its misleading statements.

Both sides in any war obfuscate for tactical and strategic reasons, but the mission to rescue Linda Norgrove had already failed when the "suicide vest" story was put out, so there was nothing to be gained from it. Its only effect was to make Linda and her family's tragedy even more bitter than necessary. And the public's waning belief in the war has slipped another notch.