Well, there you go. What a difference a week makes. President Obama, who warned scarily during the EU referendum that the UK would have to get in the “back of the queue” on trade talks if it voted to leave the European Union, has now given an interview which is remarkably different in tone on the question of Brexit.

Speaking to NPR’s Steve Inskeep, he stressed that everyone should calm down, which is good advice. The process of Brexit will take a couple of years and the whole business is not the end of the world. Norway is not in the EU and is a close ally he said. According to Obama, there’s lots of talking to come, but the basic model of liberal, market-based democracies in Europe is not going to change.

“I would not overstate it, there’s been a little bit of hysteria post-Brexit vote, as if somehow NATO’s gone, the trans-Atlantic alliance is dissolving, and every country is rushing off to its own corner. That’s not what’s happening.”

“I think this will be a moment when all of Europe says, Let’s take a breath and let’s figure out how do we maintain some of our national identities, how do we preserve the benefits of integration, and how do we deal with some of the frustrations that our own voters are feeling,” said Obama.

The President said he “doesn’t anticipate that there is going to be major cataclysmic changes as a consequence of this.”

I suspect he is underestimating the amount of upheaval, but we’ll see. Who with any confidence can say what the EU or the eurozone will look like in three years time, especially with Italy’s banks in more difficulty?

For the UK there are major risks in the City which are going to take patient, calm attention, until a new dispensation can be agreed. I hope that in time understandably disappointed Remainers who are running around saying that the world has ended, can come to see that one country saying no thanks to a relatively recent (23 ago) set of political arrangements, and the EU having (hopefully) to face up to its shortcomings, could even, you never know, turn out to be a healthy development.

There will surely be further market turmoil in the UK, as the fortunes of the negotiations fluctuate, and in the UK and beyond the asset price bubbles of the post-2008 recovery look like they are popping. This is going to be a difficult few years to navigate, but Obama is right. Hysteria is a waste of energy.