Trigger warning: this article includes positive opinions of Tony Blair. So if you are the sort of person who goes into anaphylactic shock when the former prime minister is mentioned, or burns him in effigy at the solstice, or regards his three general election victories as a historic disaster for the Labour party, please stop reading now.

Since Blair made his speech on Brexit last week, he has been attacked on any number of fronts. Predictably, he stands accused of loftily disdaining the will of the people – though his explicit point was that popular opinion can change and that the electorate should not be dismissed as a single gormless entity that grunts its assent to a hugely complex and nuanced process, then is consulted no more.

He has also been charged with sabotaging his own party, intervening as he did only days before the knife-edge byelections in Stoke-on-Trent Central and Copeland. My hunch is that neither local contest will be much affected by the speech to a pro-European thinktank in London of a man who left No 10 a decade ago. It is more likely that Blair wanted to put in his two euros-worth before the Lords debate article 50 this week, and timed his strike accordingly.

The bleak reality for Labour’s most electorally successful prime minister is that anything he says or does is going to upset certain cohorts. There will be those who will always despise him for taking Britain to war in Iraq. His own party cannot forgive him for winning, or – more specifically – for what he showed was necessary for Labour to acquire and retain power.

For those, on the other hand, who are mesmerised by Donald Trump, Brexit and the rise of the populist right, Blair incarnates everything they deplore – the globe-trotting “liberal elite” and its alleged indifference to those outside of the “metropolitan bubble”.

All this is a challenge to the institute that he and his staff are busily setting up. The report of Sir John Chilcot’s Iraq inquiry last July represented (they hope) a final haul over the coals, rather than an implicit lifetime ban from future involvement in mainstream politics.

Last September, furthermore, Blair announced that he was shutting down his commercial operation, Tony Blair Associates, which has been heavily criticised over its clientage. I was reminded of Michael Corleone in The Godfather Part III, reassuring the head of the Vatican bank that “we’ve sold the casinos, all businesses having to do with gambling. We have no interests, or investments, in anything illegitimate.”

Like Don Corleone, Blair is seeking a clean slate. He is even moving out of his plush Grosvenor Square offices to new premises. Without ditching his core values he is signalling, in every way he can, a break with the past.

It would be a mistake to imagine that our departure from the EU is all that is animating Blair.

The question is: why? Why go to all this trouble in the certain knowledge that everything you do and say will stir up controversy? Undoubtedly he regards Brexit as the clear and present danger, and a prospect that mandates his return to the political scene. But it would be a mistake to imagine that our departure from the EU is all that is animating Blair. Those who imagine that his ideas have not evolved since 1997 are allowing their loathing to cloud their observation.

Ostensibly a call to arms over Brexit, his speech last Friday was also about much else. It expressed despair at “the absence of an opposition which looks capable on the polls of beating the government”. It conceded that globalisation has spawned a series of pathologies: “communities left behind”, a rancorous debate over immigration, the crashing wave of “technological revolutions”.

The NHS, he said, was “now in its most severe crisis since its creation”. The education system urgently required an “upgrade … to prepare people for this new world”. Social care was in crisis. This constellation of problems required fresh thinking and broad horizons.

Blair’s central point was not that we should think only of Brexit, but that Brexit is preventing us from thinking of anything else. “This government,” he declared, “has bandwidth only for one thing.” Theresa May would contest this vigorously (with some justification, if you consider the weight of white and green papers that her ministers have already published). But as a broader warning against single-issue fixation, Blair’s point stands. Brexit is but one face of the polyhedron into which contemporary politics is morphing at breakneck speed.

He also drew a distinction between “arguments of detail” and “arguments of grandeur”. This was more than a rhetorical flourish. In private, Blair insists that much more empirical and “granular” research needs to be done on why different factions are embracing rightwing populism, as a counter to the sometimes lazy generalisations that have prevailed since the EU referendum and Trump’s victory. The reasons why the people of Stoke Central backed Brexit, for instance, may have little in common with West Virginians’ support for The Donald.

There is work to do, in other words. Still, that does not fully explain why Blair is heading towards the sound of gunfire, perfectly aware of the furore that lies ahead. Aren’t 10 years as prime minister and 24 as an MP enough politics for anyone?

The answer, I think, loomed over his speech. Unlike the wider left, he dismisses the idea of historical inevitability and profoundly believes in the power of human agency. Unlike the populist right, he contests the notion of light-switch moments where the electorate has the right to issue irreversible instructions.

From this premise follows a sense of responsibility, deepened by a new sense of pessimism. As he said on Friday, “for the first time in my adult life” it is no longer obvious that liberty, democracy and the rule of law are secure.

The young leader who hailed the “new dawn” in 1997 has been replaced by an older, much more reflective, much less sanguine figure. But it is to his credit that, unlike many on the embattled centre-ground, he has not yielded to fatalism.

When the remain camp needed a hero, it got Tony Blair | John Crace Read more

There will be no Churchillian return to office, nor to frontline politics. What counts is his convening power: his capacity to bring people together, to build networks of the like-minded as well as an institute in bricks and mortar.

And if not him, then who? A lesser character, hearing the rumblings of the mob, would walk away. Blair chooses to do precisely the opposite. Good for him.

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