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A little over five weeks ago, Boris Johnson bounded toward the central podium in 10 Downing Street for his daily coronavirus press briefing. At the time, 144 people had died in Britain after contracting COVID-19. Johnson opened with a joke about journalists in the room spacing themselves out in compliance with new social-distancing guidelines, then went on to say that he recognized the need to give people an idea of how long the crisis would last. The country would not be put under lockdown for another four days, but Johnson was already conscious of morale. Families were being kept apart, businesses were suffering, and people were dying. Britain, he appeared to have decided, demanded optimism.

Flanked by his chief medical and scientific advisers, Johnson said he was confident that Britain could, in 12 weeks, “send coronavirus packing.” With the public’s help in slowing its spread, he asserted, scientific progress would be able to catch up. Closing the press conference, Johnson made a revealing remark. “I’m often accused of being unnecessarily boosterish about things,” he said. “But, I genuinely think that by the combination of these two things, we will turn the tide and we will get through it.”

The comment offered a glimpse at Johnson’s character, and the kind of political calculations and discussions that happen behind the scenes in his government. Johnson’s observation about reactions to his “unnecessarily boosterish” attitude carried an implicit acknowledgement that it was not always appropriate. But on this occasion, he pushed ahead regardless. Britain was on the cusp of entering the emergency phase of the crisis, when the daily death toll would take off and the economy would be placed on life support, yet the prime minister believed the country needed lifting, not lecturing.

Johnson returned to work today, after contracting COVID-19 and taking two weeks' rest and recuperation outside London, with the same message. Appearing outside 10 Downing Street this morning, he said there were now real signs the country was on the brink of victory in the first phase of its fight with the coronavirus, even if it was too early to end the lockdown, describing the disease as a mugger that was being wrestled to the floor. Johnson finished his address with a plea for the country to keep going. Calling for a “spirit of optimism and energy,” he said: “If we can show the same spirit of unity and determination as we have all shown in the past six weeks, then I have absolutely no doubt that we will beat it; together we will come through it all the faster, and the United Kingdom will emerge stronger than ever before.”

It was a classic Johnsonian flourish. The prime minister has what one person close to him, who declined to be identified discussing internal government debates, described to me as an optimism bias, a Ronald Reagan–esque predilection for sunny uplands and better tomorrows. This is what he has built his career on. Those around the prime minister believe that it’s part of the reason for his success, and in particular his ability to understand what the public needs. His critics dismiss it as populism.

That optimism is part of what makes him a formidable politician. As London mayor, he was able to harness it to help ease national jitters about the 2012 Olympics, famously mocking then–Republican U.S. presidential candidate Mitt Romney for questioning Britain’s readiness to host the Games. Johnson pulled the same trick in a completely different guise a few years later as leader of the Brexit campaign, adopting a position of relentless optimism that his critics argued amounted to make-believe, but that many Leave advocates credit with tipping the balance in their favor.

Yet Johnson is now facing a national challenge on an entirely different scale. The question is whether such instincts can work again, or whether he needs to show a different side to his character. Within three weeks of that March 19 press conference, Johnson was fighting the coronavirus in intensive care. Since he was admitted to the hospital, thousands have died of COVID-19 in Britain, now a global epicenter for the disease, and questions have mounted over his early handling of the crisis, in particular his decision not to enforce a national lockdown sooner. Had blithe optimism hampered the country’s ability to contain it?

Still, Johnson is betting on the power of optimism to put the country back together, a political gamble that will define his premiership. Optimism at such a moment risks coming across as shallow, premature, or even inappropriate—hundreds of Britons continue to die every day, among them doctors and nurses, and personal protective equipment runs short. His suggestion today that Britain had thus far outperformed other countries, pointing to the fact that its health system had not been overwhelmed, will likely garner criticism given that overall death figures in the U.K. remain on course to be as high as anywhere in Europe. If Johnson cannot back up his optimistic framing of the next stage of the challenge, he will confirm his critics’ fiercest accusations against him—that his flamboyance masks an uneasiness with detail and precision, that he does not do the hard work that underpins leadership. The flip side of inspiring optimism is toxic positivity, a blind faith in progress even when the evidence suggests otherwise. If he succeeds, however, the path opens up for a decade of “Johnsonism” and the remaking of Britain.

The dichotomy of optimism, the power it has to inspire and to cover up, is something I have had to learn after my wife and I lost four pregnancies in 18 months. As well as the obvious pain of loss and grief, something else proved difficult to process—an idea I had about myself and the world, what one counselor with Britain’s National Health Service described to me as the superstition of good luck and optimism, that staying positive and showing energy somehow mattered against biology.

Events like miscarriages have the capacity to shake the sense of who you are and the belief systems you have constructed. The ineffectiveness of staying positive caused me to question things about myself I wasn’t even aware of. Blithely telling myself that it would be okay, that the statistics were in our favor, hadn’t helped, and might have even been actively unhelpful as the statistics changed. With each loss, saying everything would be fine was not really optimism, but a refusal to face up to the truth.

Listening to the radio one evening recently, I realized the pandemic had exposed lots of people to similar feelings. A caller on LBC, a national radio station based in London, spoke about the challenges of living in lockdown. He was finding the strange mix of isolation and claustrophobia hard, but was surprised that his wife was also struggling. She was usually so positive, he said, eventually surmising that she was “struggling with it because she’s more of a positive person than me.”

The lack of control, the reality of biological vulnerability, is difficult to accept, perhaps particularly so for optimistic people, because it challenges the very fundamentals of what they believe. Around the world, the coronavirus is taking the lives of thousands of people a day. It has killed teenagers with no underlying health conditions as well as the more vulnerable, a nurse without protective equipment, healthy doctors, social workers, and many others beside. And it almost took a prime minister—the most optimistic, energetic, forceful prime minister in recent British history.

For Johnson’s personal health crisis to affect his own instinctive optimism would be for him to question one of the fundamental facets of who he is and how he sees the world. For him to reject it, to suddenly transform into an Angela Merkel–style realist, would be to take away a part of what makes him both a formidable politician and a flawed one.

To many on the political left, belief in character and self-determination are ways of justifying privilege, and the articles of conservative faith—self-reliance, thrift, sacrifice and hard work—mere fig leaves to cover entrenched inequality. Yet those principles were at the core of the Reagan and Margaret Thatcher eras, defined by each leader’s refusal to accept what they saw as the rot of declinism that had spread through their respective countries’ political establishments. Both believed that changing course required optimism, character, and determination, not mere tweaks to the system and technocratic assessments of what was possible. Belief itself was required. Whether people consider their achievements good or bad, few would now argue that their impact was anything other than transformative.

One of the realities of the past few weeks, however, is that optimism has zero medical ability to stop the spread of a pandemic. This has been a challenge for the head, not the heart. Countries led by strong characters—Johnson, Donald Trump in the U.S., Emmanuel Macron in France—have not performed any better, and in many cases performed starkly worse, than those led by realists like Merkel.

But if it is going too far to say character is everything, it is surely also going too far to say character is nothing. Character matters, and politicians need more than just a grip on the figures to succeed. Frank Luntz, the American pollster who has known Johnson since their time as students at Oxford University, told me when I was researching a previous profile of the prime minister that he had never met anyone “so obviously talented yet so quickly dismissed by critics because he doesn't conform to their definitions or expectations.” Johnson’s skill, Luntz said, was to appeal to the heart, not the head. Andrew Gimson, one of Johnson’s biographers, told me that part of Johnson’s appeal lies in his ability to speak to people’s aspirations. “We all want, with at least part of our minds, to believe that the crisis can be surmounted,” he told me. “So Boris as leader is showing by his boosterism that he is intent on taking us where we actually want to go.”

The next phase of the crisis plays to some of Johnson’s strengths more obviously than the previous ones have, but also to some of his weaknesses. For example, Johnson has, Gimson told me, always preferred doing “a lot of things imperfectly than one thing perfectly,” choosing to press ahead on the basis of imperfect information rather than waiting until all the facts are clear. In the days and weeks ahead, this carries the risk of overreaching and overpromising—of moving too quickly based on information that confirms things he wants to be true, but might not be. Of course, this is also a reality of being in charge: As Henry Kissenger has observed, the skill of leadership is to make marginal decisions with imperfect information before others are comfortable doing so, taking a calculated gamble and being willing to stand alone first.

Today, the reality of the situation is that when Johnson was admitted to the hospital on April 5, the death toll in Britain was 4,934. Today, as he returns to work, after a week of emergency medical care and a fortnight of rest, the number of fatalities exceeds 20,000. His challenge is now to show that he can still shape the future—that optimism can inspire, character matters, and his is an asset, not a liability.

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