Pointing fingers: Miliband's suggestion that Cameron was to blame for migrant deaths counts as his first campaigning mistake

Hindsight is an extremely useful commodity for a politician who wishes to appear wise and statesmanlike. Fortunately, it is always in plentiful supply.

Ed Miliband used his keynote speech at Chatham House yesterday to make his claims to have his “finger on the trigger” of British foreign and defence policy by demonstrating his extreme wisdom, after the event, about the British intervention in Libya in 2011, and David Cameron’s foolishness over it.

No matter that Mr Cameron had little choice at the time; no matter that, in some parallel world where intervention was not attempted things might be even worse now; no matter that foreign policy is always as challenging as it is risky; no matter that France and Italy led the way; no matter that Mr Miliband voted in favour of these UN-authorised air strikes against Gaddafi – Mr Miliband just couldn’t resist the temptation to say “I told you so”.

It was pretty contemptible stuff, and the first serious misstep in what has previously been an assured campaign performance.

Having garnered public sympathy after the nasty attacks on him and his family by the Tories and their media allies, and gaining some respect in the process, Mr Miliband needlessly gave the impression, at least, that he wanted to blame the Prime Minister for the deaths of thousands of migrants in the Mediterranean. That he rowed back hours later could not erase the initial error.

According to Mr Miliband, Britain has repeated the same mistakes “in post-conflict planning” for Libya as were made in Iraq, and, therefore, helped to cause the current refugee crisis. Maybe, though the flood of refugees from civil wars across West Africa, East Africa, the Maghreb and the Middle East are the product of a series of previous failures of post-conflict planning, not least regarding the war in Iraq after the Anglo-American invasion of 2003.

That, it must be recalled, was a conflict supported by Mr Miliband when he was making his way up the Labour Party’s greasy pole, and only definitively repudiated as he went for the party leadership in 2010. Some said that it was a cynical move to win a tactical advantage over his brother, David, who couldn’t so easily disown the policy; even if his brother wasn’t, the Blair government was betrayed. That 2010 U-turn certainly had the benefit of hindsight.

So, an unexpectedly scrappy end to a week which had started well for Labour. The polls, to use a technical psephological expression, are all over the place, and, even if they weren’t, making a reasonable prediction of the make-up of the next House of Commons on 8 May is as difficult as ever. Labour was never sure of winning, to say the least, and it has lost some momentum.

Meantime, with their English Votes for English Laws initiative, the Conservatives are starting to exploit further the resentment against the SNP’s prospective influence at Westminster, which they have been pushing these past few days. That is a very dangerous game, risking the future of the Union for the sake of short-term political advantage. (Just as Mr Cameron is similarly risking our place in the EU – something Mr Miliband was at least admirably forthright on in his Chatham House speech.)

If it shows one thing, though, it demonstrates that the Conservatives can still be much nastier, and indeed, reckless, in the pursuit of power than Mr Miliband, even when Ed puts his considerable mind to it.