Mark Steel: Labour's leadership candidates are all against the war now

There's an honourable tradition in the Labour Party of bravely standing against an unjust war – as long as the war ended several years ago. So, one by one, Labour's leadership candidates are announcing their opposition to the invasion of Iraq, just in time for it all to end. Labour leaders did a similar thing after the Vietnam War, and the First World War, and at the moment they all support keeping the army in Afghanistan, but I bet they haven't a good word for the Second Crusades, which is the main thing.

Maybe the whole anti-war movement should follow this example, as it would make people feel more effective than campaigning against wars still going on. Imagine how powerful demonstrators would feel if they held a Stop the Crimean War march. Someone could announce at the rally afterwards that it had indeed stopped, 160 years ago. Then, instead of the usual feelings of impotence, everyone would go home delighted.

Ed Balls and the Milibands have distanced themselves this week from the war they supported, so to get ahead Ed Miliband will now say he's going on the march, adding that he would have gone on it at the same time as everyone else seven years ago but he was waiting in for a wardrobe to be delivered and it's only just come.

Ed Miliband now says he "believed the UN inspectors should have been given more time," although he doesn't appear to have said this back then, presumably as he was saving up this comment for when it really mattered. Next he'll say "and I'm a firebrand on the Corn Laws now I've made my mind up". And David will say: "I did vote for the war, but I had a dream that me and a squirrel were stuck in a windmill in Basra, which shows that my subconscious was firmly against it."

David Miliband, the only one lucky enough to be an MP at the time, says he supported the war because of evidence of Saddam's famous "weapons", adding he would have opposed it "if we had known then what we know now". But the only reason people believed Saddam had those weapons was because Miliband's government was telling everyone he did. So, he's saying: "If I'd known I was lying it would have been different, but how could I possibly know I was making stuff up? You can't blame me for fooling myself, as I'm very persuasive."

David Miliband is also accused of being complicit in handing suspects over to be tortured, so maybe he'll try a similar defence, saying: "If I'd known at the time that torture could include pain I would never have approved of it. But someone told me electrodes were more tingly than unpleasant, like one of those strange chairs that massages your back. Still, you live and learn."

Something similar has happened on other issues as well, so ministers who've advised and voted in favour of making their party friendly to the City are now appalled by the greedy bankers they spent 15 years admiring. It was all done to place Labour in the centre, but what they didn't see is that the centre can change place, and what was once seen as extreme, such as opposing wars and despising bankers, is now mainstream.

Otherwise why would they all have discovered the war was wrong right now? Even a month ago they said nothing, so they've all just changed their minds, have they? Some people might suspect they've decided to oppose the war because they figure this will help them get elected as leader, and they supported it before to help their careers, and the effect of their decisions on the fate of millions of people has played no part in their judgement at any time. But that would be cynical so let's just accept it must be a coincidence.

But also, there were plenty of others who weren't fooled by the shady evidence, so surely the Labour Party would do better to entrust the leadership to people who weren't so easily duped. There's contender John McDonnell, who opposed the war from the start, and others include Damon Albarn, Zoe Ball, Chris Eubank, Leo Sayer and Jimmy Hill, who should surely form the basis of a far more principled, astute and imaginative shadow Cabinet.