The heckles in the House of Commons can be as revealing as the speeches. When the prime minister was taking questions about her Brexit plans on Monday, Anna Soubry, Conservative MP for Broxtowe, asked about the no-deal scenario – whether the UK would “jump off the cliff”. At which point a male voice, dripping with derision, chimed in: “There is no cliff!”

Hansard doesn’t record the source of the intervention. It could have been one of dozens of Tories who despise talk of cliffs. The prime minister is not among them. She has been taken on an illustrated tour of the edge by her advisory council of business leaders. They describe the elevation and the effect of high-velocity impact: the return of customs controls; barriers to trade; the rupture of supply chains; investors rerouting money and jobs to the continent.

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May had come to the Commons fresh from a meeting with those experts in economic gravity, and duly restated her intention to negotiate an “implementation phase”, to run for two years after departure day. It will look rather like EU membership, with mutual market access “on current terms”. Hardliners hate this idea, smelling betrayal – a plot, driven by the Treasury, to enact “Brexit in name only”. They mistrust the prime minister’s assurance that she is only easing the outward path. But they also don’t want a parachute because they crave the giddy surge of adrenaline that comes from a giant leap.

There is a contradiction here that the likes of John Redwood and Bernard Jenkin do not acknowledge, perhaps even to themselves. To make “no deal” sound acceptable, they must belittle the scale of upheaval, yet the only reason for accepting it would be to accelerate drastic change. They do not acknowledge the cliff but they dream of launching from its edge, soaring over the Atlantic once the EU shackles are broken.

The psychology of this is rooted in pre-Brexit Conservative folklore. It starts in veneration of Margaret Thatcher’s pugnacious dismantling of state-run industry in the 1980s. I don’t intend here to relitigate the case for and against those reforms. The point, for the Brexiters, is not whether Thatcher’s vision was the best one (this is beyond question in Tory theology), but that it could be done only by economic violence. The status quo needed smashing.

Tories have subsequently defined political heroism as willingness to inflict tough love. As John Major put it in 1989, when serving as Thatcher’s chancellor: “The harsh truth is that if it isn’t hurting, it isn’t working.” He was talking about controlling inflation, but the maxim has become liturgy in the church of Conservative radicalism.

Interrogate the Brexit no-dealers on detail and they concede that their plan hinges on a doctrine of pain for gain. They advocate the abandonment of tariffs, inviting the world’s exporters to flood Britain with their wares. Thus would a beacon of free trade be lit on Albion’s shores, inspiring others to repent of their protectionist tendencies. This might bring cheap produce to supermarket shelves (consumer gain) but sabotage UK farmers, who would be undercut by an influx of American and Antipodean meat (producer pain).

Manufacturers would suffer too, but that is an intended consequence of opening the doors to invigorating winds of competition. The whole point is to sweep away inefficiency and blow down zombie businesses while fanning the flames of innovation. In this model, the UK economy is a vast pre-Thatcher coalfield that refuses to accept its obsolescence and must be made to confront it by force. If the timid will not jump into the future, they must be pushed.

There are countless problems with this, not least the inane strategy of unilateral economic disarmament, surrendering upfront any leverage with the US and others ahead of trade talks. Britain already has an open, liberal, globalised economy. It has problems with low productivity, an underpaid workforce, patchy infrastructure and, thanks to Brexit, regulatory uncertainty. It is unclear how those issues are addressed by setting fire to agriculture and industry, then waiting for phoenixes to rise from the ashes.

What fascinates me is hard Brexiters’ blindness to the political consequences of a pain-for-gain doctrine. Have they not visited places where voting Conservative is culturally taboo? Do they still not understand how the experience of rapid deindustrialisation produced anti-Tory allergens in the communal bloodstream? Can they not imagine the anger of people who feel pain without the gain?

For a party so doctrinaire about markets, the Tories are strangely uninterested in the balance of supply and demand in the business of government. They have spent seven years cutting the supply side and waiting for demand to shrink too. But people are stubbornly attached to the idea that politicians should help them through hard times. Voters might resent high taxes and unresponsive public services, but the idea of the state as the enemy is the preserve of an ideological fringe.

They want to set fire to the UK’s agriculture and industry, and then wait for ­phoenixes to rise from the ashes

A lesson of the past few years is that fear of economic abandonment stokes protectionism and nationalism. Backbenchers warn darkly of a public backlash if the Treasury is allowed to dilute Brexit, but it is hard to think of a better formula for inflaming Trumpian rage than the brutal shock accompanying the no-deal scenario. The smarter leave campaigners knew the limited appeal of turbo-Thatcherism, which is why they pretended that £350m would be available to subsidise free public healthcare. It wasn’t that they couldn’t fit “We will break up the NHS at the behest of vast US corporate lobbies” on the side of a bus.

And at no point did leave campaigners claim that a deal with the EU was dispensable. They said it would be easy. Only when the cliff comes into view do they start denying its existence, while reaching to grab the wheel from Theresa May to steer towards the edge. As it gets closer, they will switch to saying the leap is necessary and good – that Brussels has blocked the roads, that the icy water below has restorative properties, that Brexit must hurt to work. But for whom? There will be a tiny minority exhilarated and enriched by the ride. The rest will see what is really going on: that we are not flying but falling.

• Rafael Behr is a Guardian columnist