Striding to the stage in a room filled with his rabidly Eurosceptic cheerleaders, Boris Johnson perfectly captured the tenor of the times, having been introduced by every Tory’s favourite bass-baritone, Geoffrey Cox.

Johnson launched his leadership bid with a fictional plan for Brexit. He has promised to shred the withdrawal agreement negotiated by Theresa May, claiming that he can secure a better Brexit deal. EU leaders might have said they will not reopen the legal text, and have even disbanded the negotiating team in Brussels, but Johnson claims he can defy this political reality. There is little reason to believe this is true.

The central plank of Johnson’s fictional plan is to use the £39bn financial settlement as negotiating leverage. He talks as if it were sitting in a bank account somewhere, waiting to be spent, as if it were an arbitrary fee to exit, rather than the settlement of obligations arising from membership. In fact, much of it comprises the UK’s net budget contributions for 2019-20, the years that were supposed to be for transition. It includes the settlement of liabilities accrued over nearly half a century of membership, and spread 60 years into the future. It is simply false that it is negotiating leverage.

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Unwittingly, Johnson began his speech extolling the benefits of EU membership by commending the strengths of the British economy, which remains in the EU. But perhaps his most bizarre claim was that Britain will have more leverage by being better prepared for no deal. Johnson will tell EU leaders that Britain is prepared to cut off its nose to spite its face because it has a pile of bandages at the ready. In truth, no deal would be bad for the EU but far worse for us. The European single market accounts for nearly half our international trade; for no major EU economy does the UK account for more than 10%. Moreover, UK trade with dozens of other countries is structured through EU trade agreements. It would be like placing sanctions on ourselves.

The entire endeavour is powered by self-belief. Johnson promised that “total conviction” would transform the negotiations, which he has said will be led by ministers rather than officials. No doubt the hardliners in the Tory party will be delighted at his intention to ditch Olly Robbins, the chief civil service negotiator. Diplomatic experience and command of details are to be replaced by swagger, led by a prime minister only prepared to “answer” six questions from the press. And whatever criticisms were made of Theresa May, a lack of tenacity was never one of them. It is simply delusional to imagine that a more combative approach will yield better results. If anything, it will achieve the opposite.

Above all, Johnson said that “after three years and two missed deadlines we must leave”, even if that means no deal. He claimed that “delay means defeat” and yet no delay means no deal. In any case, it is apparent that parliament will block such an act of national vandalism, with parliamentary manoeuvres already under way to prevent it. In response to a question about how he would get to no deal in the face of parliament’s opposition, all he offered was hot air about “the will of the people”. If it looks as if Johnson is about to take the country over the cliff edge, then parliament looks highly likely to instruct the government to request an extension to the article 50 period. It may even legislate to give the people the final decision on Brexit, or perhaps revoke article 50 altogether.

Johnson knows all of this. So a Brexit plan founded on fiction rather than fact probably isn’t the plan at all. It seems that his isn’t a strategy to achieve a better deal, but rather to create a collision with reality from which he will benefit. Perhaps the goal of his plan is to provoke a confrontation with the EU, while sounding reasonable to a domestic audience. That’s why he calls no deal a “last resort”, and has promised both to discuss the Irish border as part of the future relationship and to unilaterally recognise the rights of 3.2 million EU citizens living in the UK. The intention is to set the stage for a snap general election in October, where he will blame an intransigent and unreasonable EU – the same game he has played for nearly 30 years.

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If an October general election does occur, no deal will in all likelihood be the Conservative manifesto, a political imperative created by the rise of the Brexit party and by May’s years of foolish posturing that “no deal is better than a bad deal”. Expect Nigel Farage to stand down his army of Brexit extremists once he has achieved his goal of radicalising the Conservatives. Meanwhile, Labour’s strategic dithering could turn out to be a colossal error. If the right unites but progressive remainers splinter between Labour, the Liberal Democrats and Greens, then Johnson could be handed victory.

Johnson surely knows that a no-deal exit will be painful, but probably believes that the experts’ forecasts are exaggerated. Besides, he no doubt reasons, he will have five years as prime minister to turn things around and he has a friend in the White House to help him. Yet in truth, there is no such thing as “no deal”. There is an orderly path or a chaotic route to arrive at the same destination: the negotiated withdrawal agreement.

If the UK exits without a deal at the end of October, then a pre-condition of any trade talks will be acquiescence to the Irish backstop and settlement of the financial obligations of our nearly half-a-century of membership. How many weeks of self-inflicted chaos could any government endure before coming to terms with reality? If there is one clear lesson from the past three years, it is that it is unwise to deduce method from madness. Sometimes idiocy is all that there is.

• Tom Kibasi is director of the Institute for Public Policy Research