It probably doesn’t say much for the prospects of the hardcore counter-Brexiteers if Tony Blair ends up their highest-profile champion.

His rallying cry in the New European newspaper is a demand that the British public should be given the ‘opportunity’ to think again about leaving the EU, once we have “a clear sense of where we’re going”.

This is a fairly standard Remain argument: “Yes, we voted for Brexit, but what does Brexit mean? Hm?” But this argument cuts both ways – how many people voted Remain to avert the ghastly spectres of immediate economic collapse conjured up by George Osborne et al?

But set that aside and Blair has a much more important problem, which is the fact that he’s complaining about a process for leaving the EU that his own New Labour Government (with Gordon Brown closing the deal at the very end) signed up to.

Article 50 is a one-way exit corridor with a punishingly short timeframe for negotiating a new set of terms. It was never intended to be a constructive way out for members who wished to leave the bloc – leaving isn’t meant to happen. Rather it was explicitly designed to be the opposite.

It was contained in the Lisbon Treaty, which was signed by the Member States on December 13 2007 only months after Blair had handed the keys to Number Ten to Gordon Brown, at a special Labour conference in June of that year.

Had they wished to, New Labour could have fought for a more constructive, less punitive mechanism for departing the bloc. It could have had just the opportunities for reflection and reconsideration that Blair pines for today. But there is no indication that he did any such thing.

As Andrew Rawnsley notes, the EU referendum result must have a particular sting to Labour’s most electorally-successful Prime Minister because it represents the shattering of the last of the “pillars of Blairism” – support for liberal interventionism abroad and an election-focused, centrist Labour Party having toppled already.

Many have pointed out that the blame for Brexit, or at least a substantial portion of it, can be laid at the feet of New Labour. It was on their watch that the eastward expansion of the EU, combined with its ministers own laxness, lit the fuse under the issue of immigration. Blair’s oft-promised but undelivered referendum on a European question made one much more likely, and at a much more disadvantageous moment for the European cause.

But let’s not lose sight of the fact that it was Blair, and latterly Brown, who signed Britain up to the treaty which made the decision to leave so decisive and hard to reverse.