So where do we go from here? What does Emmanuel Macron’s victory in yesterday’s first round of the French Presidential elections mean for France? What does it mean for Europe? Most important of all, if you’re Theresa May, what does it mean for Brexit?

For France, it means that the next occupant of the Elysée Palace will almost certainly not be an extremist. the two big parties, the Républicains and the Socialists, have been humiliated, but not broken. They have, to coin a phrase, been told by the electorate to go home and think again.

Suddenly, insurgents are yesterday’s news. The age of eruptive populism looks to be drawing to a close. First in Austria, then in the Netherlands, now in France, demagogues of the Far Right have been stopped in their tracks. While it might be too early to say that normal service has been resumed, the abnormal is in retreat.

Assuming Macron wins the Second Round of the election on May 7 – and the polls suggest he will beat yesterday’s runner-up, Marine Le Pen of the Front National, by a substantial margin – the new President will be moderate, focused and emphatically pro-European. No one should be surprised by this. Though he has himself been labelled a populist, the 39-year-old is in fact the ultimate insider. A former investment banker and a product of the École Nationale d’Administration, he was exactly the man the French Establishment needed to shore up the ancien régime. 

Until they regroup, both the Conservative centre-right and the Socialist centre-left are rudderless. Francois Fillon, though he fought a doughty campaign, can now spend more time with his lawyers. Benoit Hamon, the PS candidate, can only lick his wounds. Macron’s biggest problem, once he has definitively seen off the challenge of Mme Le Pen – or “Marine” as she prefers to be known these days – will be to do something resolute and effective to tackle Islamist terrorism while submitting a programme of economic reforms that gradually boosts competitiveness without utterly antagonising the trade unions.

How effective he will be in overcoming the immense resistance of France when exposed to change, however modest, is something else. No one expects him to achieve a Bake-off-style revolution in his first year. They just hope that he can make progress and that he has that most elusive of qualities in public life – luck. What is certain is that a Macron triumph in the polls on May 7 will cast a shadow over the bonne continuation of the British prime minister on June 8.

For the European Union, Macron and his En Marche movement are the dream ticket. Motivated by a deep commitment to the European Project, he sees his country and the EU advancing hand-in-hand. Over and over again in his victory speech, he conflated the two, talking of the them as if they were one and the same. He wishes to see Europe reformed; he wishes to see it modernised. Mais bien sûr. But he has no time for those who wish to bring it down. On the contrary, he wishes to usher it into a new age of plenty. As he told audiences and journalists throughout his campaign without the slightest hint of embarrassment, what he wants is more Europe, not less. 

Which brings us to Brexit and the British. Macron is an Anglophile. He speaks fluent English and often visits London. But the Britain he admires is the Britain of bankers, Adele and Tony Blair, not that of Nigel Farage, David Davis and what he perceives as Little England. He is both mystifed and dismayed by the UK’s decision to quit the EU and is sure to add his support to Angela Merkel, Donald Tusk, Jean-Claude Juncker and Guy Verhofstadt as they seek to rally the 27 against the virus of nationalism. 

For Marine Le Pen, Macron’s victory is surely the beginning of the end. She will not go quietly. She will do everything in her power to attract votes in the second round from disaffected Conservatives and blue-collar Leftists who flocked first time round to the Marxist Jean-Luc Mélenchon. But her numbers simply do not add up.

It had been assumed that she would win some 25 per cent of the first round vote and go into the decider with the wind in her sails. Instead, Macron came first, polling nearly 24 per cent to her 22 per cent, followed by Fillon and Mélenchon in a highly-respectable joint third place and then by the Socialist candidate Benoit Hamon, trailing home home a distant fifth.

Nothing is impossible. Miracles do happen. But if last week’s highly-publicised murder of a police officer on the Champs Elysée, and the wounding of two of his colleagues, could not persuade fear-driven doubters to give the Far Right leader their vote, what will? For Le Pen to stage a comeback, she would have to garner more than half the votes of those whose leaders to a man have refused to work with her. Fillon and Hamon have already pledged their support to Macron, and only a minority of Far Left voters can be expected to hold their noses and vote for Le Pen.

Macron’s biggest challenge is likely, in fact, to come in mid-June when the elections to the National Assembly fall due. He lacks party organisation. Indeed, he lacks a party. His operation is largely screen-based, which works better in a tightly-focused presidential campaign than on the ground, where 577 contests have to be fought over two rounds of voting. The Republicains and Socialists, both with well-oiled electoral machines, can be expected to go all-out in the battle for seats, hoping to achieve a cohabitation that, in the long run, works in their favour. Under the constitution, the President is obliged to choose his prime minister from the largest party in Parliament, and, short of a miracle, it is difficult to see how that could be En Marche. 

Against that, parties, and loyalties, in France are fluid. Names and structures are not engraved in stone. It could be the case that a hastily created Macronist bloc will ally with a swathe of Fillonistas and “progressive” Socialists to provide a basis of support, at least in the short term. Could Manuel Valls, François Hollande’s prime minister for three of the last five years, be his choice to head the government? It is not impossible. Stranger things have happened. 

Even without a majority, Macron, if confirmed as President, will still have ultimate authority in the key areas of foreign policy (including Europe), defence and national security, and in his first year could hope to ward off most assaults. And if he couldn’t, who knows? Perhaps the shrewdest move the new President could make would be to work with what he has until the nation’s patience expires and then call for an end to the creaking Fifth Republic itself. De Gaulle reinvented France. Perhaps it’s time for an update.

I said earlier that populism was dead. What was perceived only weeks ago as the -ism that would define a post-globalist world is already in retreat. Donald Trump in America is struggling, unable, or unwilling, to live up to promises that he probably never expected he would have to keep. Brexit in the UK is turning out to be just that – a unique decision by the British people, achieved via a wafer-thin majority, to revert to type by going it alone and leaving the rest of Europe to get on with its business.

I should add one caveat. however. In his person, Macron may actually represent the last spasm of insurgency – one that appeals not to the extremes but to the morally-ambiguous centre, grounded in the “patriotic” values that yesterday were given mischievous expression by none other than Anthony Charles Lynton Blair. It would be premature, if tempting, to dismiss Macronism as a passing fad, lacking in substance, inflated by cheap rhetoric. But even if that should prove to be the case and he is turfed out of the Elysée at the first opportunity, his momentum should last long enough to put an unwelcome spoke in Theresa May’s Brexit wheel.

She should take note and prepare accordingly.