Boris Johnson enters 10 Downing Street.Hannah McKay / Reuters

What has stopped Britain from leaving the European Union, three years after it voted to do so? Is it the difficult negotiations over the Irish border? The cold facts of parliamentary arithmetic? Or is it the nebulous nature of Brexit itself, wherein 52 percent of Britons delivered a vague mandate to Leave and left it to politicians to fill in the details?

No, according to Boris Johnson, Britain’s new prime minister; it is none of those things. Outside 10 Downing Street today, he identified the real barrier to Brexit: a lack of optimism.

“It has become clear that there are pessimists at home and abroad,” said Johnson, bouncing on his heels with the enthusiasm of a Labrador. He attacked the “doubters, the doomsters, the gloomsters” who do not believe in Britain’s glorious post-Brexit future or its ability to reach those sunlit uplands. “The people who bet against Britain are going to lose their shirts,” he added.

These stirring yet vague demands for positivity were a regular feature of his campaign for the Conservative leadership. His final column for The Daily Telegraph—one he was paid £250,000 ($312,000) a year to write—argued that more “can-do spirit” was needed to resolve a puzzle that has tormented Parliament for months. After all, he wrote, “if they could use hand-knitted computer code to make a frictionless re-entry to Earth’s atmosphere in 1969, we can solve the problem of frictionless trade at the Northern Irish border.” (It was left to scientists to point out that Apollo 11’s reentry was not “frictionless”—that is why it had heat shields. Johnson might also have mentioned that the moon mission was the culmination of years of intensive planning and preparation.)

To the 90,000-odd Conservative Party faithful who elected him (a “selectorate” that forms less than 1 percent of the British population), none of this matters. Johnson has told them that everything is going to be okay, and they want to believe him. More than anything else, they are bored with discussions of trade deals, nontariff barriers, and regulatory orbits. He promises entertainment and novelty instead. In this reading, the greatest flaw of Theresa May, Johnson’s predecessor on Downing Street, was not just failing to pass a Brexit deal, but doing so in such a dull, repetitive fashion. The possibility of a No-Deal Brexit is exciting, in the way that stories about the Second World War—and Johnson’s hero, Winston Churchill—are exciting. It is a viewpoint that can flourish only now that so few people remember the reality of that time: rationing, air raids, death. There’s a reason that “May you live in interesting times” is considered a curse.

Johnson’s addiction to optimism is reminiscent of Donald Trump’s promise of endless victories. “We’re going to win so much, you’re going to be so sick and tired of winning,” the U.S. president said in April 2016. The new British prime minister offers a similarly enticing prospect: a world without compromises or awkward concessions, a world where Britain is once more recognized as a great power (back to the Second World War again). It is patriotism on protein powder.

So perhaps his No Deal preparations, directing the civil service to ramp up planning for such a scenario, are not a bluff. Today, he repeated his campaign promise to leave by October 31, with or without an exit deal, “no ifs, no buts.” (It is a phrase with an unhappy history: Former Prime Minister David Cameron used it in 2011 when making his pledge to lower net migration into Britain to fewer than 100,000. He failed repeatedly.)

The rest of the speech proved that he has two modes: buffoonery and boredom. It was light on jokes. There was, mercifully, no Latin. It merely dabbled with the self-satisfied wordplay that filled his newspaper columns, such as calling the four nations of the United Kingdom the “awesome foursome.” Parts of it sounded like May’s own Downing Street speech after she became prime minister in 2016: high aspirations about social justice, all eaten by the relentless grind of European negotiations.

The tragedy of May’s speech three years ago was that it barely mentioned Brexit, the issue that consumed her premiership and led to her downfall. At her last Prime Minister’s Questions today, she tried again to create a different legacy. She saw her success in “the opportunity of every child who is now in a better school, in the comfort of every person who now has a job for the first time in their life, in the hope of every disadvantaged young person now able to go to university, and it is in the joy of every couple who can now move into their own home.” This is how she would measure her record, she said. She will be the only one to do so. To history, May will be the prime minister defeated by Brexit.

Will Boris Johnson be remembered the same way? His insistence that he is prepared to leave the EU without a deal—risking interruptions to food and medicine supplies—has already prompted several senior members of the cabinet to quit. They include International Development Secretary Rory Stewart, who coined the most durable sound bite of the Conservative Party leadership contest that Johnson eventually won. When Stewart tried to stuff three garbage bags into his bin at home, he said, his wife told him off. Instead of accepting that she was right, he was tempted to tell her, “Believe in the bin!” Brexiteers had a similar approach, trying to magic away problems by declaring, “Believe in Britain!”

The past few weeks have been very “believe in the bin.” The cabinet has been reshaped with the appointment of hard-line Brexiteers such as Dominic Raab, who resigned as Brexit secretary because he saw May’s deal as too weak—and has called for Parliament to be suspended if it refuses to accept a No-Deal Brexit.

“In 99 days’ time, we’ll have cracked it,” Johnson announced this afternoon. “The British people have had enough of waiting.” Except, of course, they have a little more waiting to do. Parliament breaks up for the summer tomorrow and does not return until September. If Johnson has a new deal, it will be more than a month before we find out whether it can pass the House of Commons.

“To all those who continue to prophesy disaster, I say yes—there will be difficulties, though I believe that with energy and application they will be far less serious than some have claimed,” said Johnson. We live in interesting times.

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