Are we seeing the death of political optimism?

Yes, we can. Things can only get better. Wir schaffen das—or as Boris Johnson translated it from Angela Merkel’s original German, “we can do this.”

What all these political slogans have in common is that they’re optimistic, positively brimming with confident, can-do spirit. They may sound suspiciously vague, but voters buy into such expressions of self-belief, if only because it beats being told that one’s country is sinking into a decline that nobody quite knows how to reverse. Even when the prognosis is the same, doctors with cheerily optimistic bedside manners tend to reassure patients more than doom-laden ones. Research has suggested optimists may find it easier than pessimists to get a job, and get promoted faster, perhaps because their belief that problems can be overcome encourages them to find solutions, or simply because they’re cheering to have around. So it’s not surprising that optimists also tend to win elections too—or perhaps more accurately, they used to.

In choosing Johnson as their leader, Conservatives bet the House on the feelgood power of optimism after years of gloomy austerity messages and humiliating compromises over Brexit. Where Theresa May stirred voters’ pity, struggling dutifully to achieve the impossible, her sucessor oozes joy at having the job he always wanted, plus breezy confidence about what he’ll be able to get done. Even his willingness to spend money, something voters instinctively associate with boom years, sends a subconscious message that things must be better than they look. Johnson’s audacious move to prorogue parliament for five weeks—effectively daring Remainers to bring an early vote of no confidence and election for which they’re seemingly not ready—looks equally designed to convey the illusion of boundless confidence. It disguises the fact that the fundamentals which defeated his predecessor have barely changed. But the cliché that hope triumphs electorally over fear now carries hefty caveats.

Belief in the political power of optimism rests heavily on a now iconic study by the American psychologists Harold Zullow and Martin Seligman, which found that the presidential candidate who had the more upbeat acceptance speech to their party convention went on to win the vast majority of US elections between 1900 and 1984. Tellingly, however, three out of the four exceptions to the rule fell during the Great Depression and its aftermath, suggesting that optimism may backfire when too detached from grim reality. For many voters, Johnson’s insouciance in the face of a no-deal Brexit sounded more unhinged than cheering.

That is not, however, the only caveat. Seligman himself has acknowledged that his theory only holds up to the Reagan era. According to their optimism scores, Michael Dukakis should have beaten George HW Bush in 1988—and Hillary Clinton would be in the White House today. Either the theory is wrong, or something about the methodology is out of date.

One explanation is that voters’ impressions are now formed as much by viral social media clips or by candidates’ life stories as by the formal speeches Zullow and Seligman analysed, and these don’t always tell the same story. While Trump’s convention speech portrayed America as spiralling into violent decline, his broader campaign message was one of boundless belief in his ability to make it great again. Everything about the self-glorifying way he presents himself, and his personal story, is of a piece with that.

Another explanation is that liberals can underestimate the ability of politicians fuelled by fear and hate to none the less embody hope and optimism for their supporters. Voters of colour, or women unnerved by a series of sexual assault allegations, understandably saw Trump as a threat. But his base saw someone promising to bring back jobs, self-esteem and “simpler times,” less anguished and apologetic.

Similarly in Britain, those who associate Brexit solely with the whipping-up of xenophobia or the grumpy rejection of the 21st century miss the hope many Leavers saw in it, however false the promise may be proving. Vote Leave talked about prosperity, freedom, £350m a week for the NHS and a chance to be heard, plus took a can-do attitude to overcoming associated difficulties that made the Remain camp’s entirely legitimate warnings sound defeatist. Casting leavers as Project Hope and Remainers as gloomy Project Fear was one of Dominic Cummings’s smarter tricks, and one his new boss in Downing Street will surely seek to repeat in an election campaign.

Yet some of May’s former staffers note the similarities between Johnson’s exuberant honeymoon period and their own early months in power, when so long as May promised to make a success of Brexit she could seemingly do no wrong—right up until she almost lost an election. What they had missed—since to them Jeremy Corbyn was an object of fear and derision, not a beacon of hope—was an equally infectious enthusiasm for Labour’s promise to remake the economy. However downbeat Corbyn’s language can sound, his insistence that he could afford free university tuition fees, a well-funded NHS, a solution to the housing crisis and much, much more with just a few modest tax rises was as optimistic as anything May ever said, but sounded more uplifting to younger voters.

That is a reminder that polarised electorates don’t all hope for the same thing. When Britain goes back to the polls, the real question may not be whether hope trumps fear, but whether we still agree on which is which.