So, you’ve finally landed the job you’ve been dreaming about your whole life. But, damn it, there’s a catch. In order to land it, you had to promise a whole bunch of people something big. And now it turns out — not altogether surprisingly, your critics say — that’s going to be difficult, if not impossible, to deliver. And even if, by some miracle, you do end up delivering it, an awful lot of people are going to hate you for it. Even worse, some of those who thought they’d love you for it are going to find that it doesn’t help them anywhere near as much as you said it would. It may even make their lives worse.

No, I’m not talking about President Donald Trump and his beloved border wall. I’m talking about British Prime Minister Boris Johnson and his push for a “no-deal” Brexit (under which the U.K. leaves the E.U. without any kind of negotiated agreement over borders, tariffs and the like).

The next couple of months could see Johnson emerge as a conquering hero to Britain’s pro-Brexit voters, or one of the country’s shortest-serving prime ministers.

Back in July, Johnson won the contest to replace Theresa May as head of the Conservative Party (and therefore PM) by insisting that the U.K. leave the E.U. by the deadline for departure set for Oct. 31 — with or without a deal — after she tried and failed to hammer one out. But whether he’ll succeed is anyone’s guess, and that’s never a good situation for the leader of a country to be in. The next couple of months could see Johnson emerge as a conquering hero to Britain’s pro-Brexit voters, or one of the country’s shortest-serving prime ministers. In other words: It’s all or nothing.

May at least got three years before she had to face the music. During that time, she painfully tried to reconcile various irreconcilables. Most obvious was the Conservatives’ desire for a close economic relationship with the E.U., Britain’s biggest trading partner, even after it departed the economic and political bloc so that E.U. citizens could no longer freely live and work in the U.K. The other was to prevent the need for a hard border between the Republic of Ireland and Northern Ireland, which is part of the U.K.

May’s biggest mistake, however, was to coin the fateful slogan, “No deal is better than a bad deal” — one that gradually morphed, among Leave-voting Conservative members of Parliament who had promised the public a quick deal, from a management-textbook cliché into a full-blown mantra that spelled her downfall.

When she came up with a withdrawal agreement that involved too many concessions, they blocked it and forced her to resign. The Conservatives, then, had failed to deliver Brexit and looked hopelessly split. Upended by Nigel Farage’s new Brexit Party in elections to the European Parliament in June, they won less than 10 (yes 10) percent. Threat level to the Conservative Party: existential.

Johnson himself, however, had been smart enough to resign from May’s administration so as to avoid any responsibility for the mess. And he’d used the time to consult with erstwhile Trump aide Steve Bannon on populist and culture war techniques, which then boosted his profile and mobilized the right-wing membership of the Conservative Party — all of which helped him win the post-May leadership contest in July.

Having won it, his mission is clear. He has to get the U.K. out of the E.U. by the end October if he is to ensure that voters who deserted to the Brexit Party return home to the Conservative Party. And if that means, as it almost certainly does, leaving without a deal, then so be it.

His problem? Most MPs (including, as he well knew, a number of his own Conservative colleagues) won’t countenance that and made it clear they would pass legislation forcing him to ask the E.U. for an extension to the deadline. His response? To bend (but not break) the rules of Britain’s unwritten constitution by effectively obliging the poor old queen to prorogue (temporarily suspend) Parliament and cut down the time available for Conservative rebels to do that.

Their response? To pass the legislation over the course of just a few days before the suspension kicked in. His counter-response? To use the passing of that legislation as an excuse to call for an early general election on Oct. 15. Whether Parliament will eventually grant him his wish (they refused his first call for one today) is by no means certain.

In the end it will be up to the opposition Labour Party, many members of which (including former leader Tony Blair) regard it as a trap that they should avoid because, even though the opposition is supposed to grab any chance it can to replace the government in office, the party is pretty unpopular right now. If they do, however, polls suggest Johnson stands a reasonable chance of winning. And, if he wins, he will be able to claim a mandate to take the U.K. out of the E.U., with a deal or without one.

If that isn’t enough to scare the E.U. into making 11th-hour concessions, Johnson argues that Britain will be fine because the government is spending untold millions on preparing for a unilateral Brexit and his best buddy, Trump, will fast-track a lucrative trade deal that would supposedly make up for any business lost with Europe.

That’s still the plan. And it just might work. But it comes with massive risks.

If Johnson genuinely cares about the national interest, then a new independent report on the serious, across-the-board harm a no-deal departure could well do the country should surely give him pause. It suggests not only disruption, but a decline in trade and economic activity resulting in significantly slower growth that can’t be compensated for by deals done with other countries.

But even if partisan advantage is all Johnson cares about, he should be careful what he wishes for. Right now, no-deal is the preferred option of only just more than half of Conservative voters and a mere quarter of all Brits. And should it actually happen and turn out to be a disaster, it could constitute a career-terminating event for those politicians seen to be responsible.

Right now, no-deal is the preferred option of only just more than half of Conservative voters and a mere quarter of all Brits.

True, if Johnson can engineer an election before no-deal happens — if it happens — then a heady mix of nationalism, populism, tough-on-crime rhetoric, hostility to migration and multiculturalism, and the splashing around of plenty of borrowed cash might lend him victory.

Yet, long term, that kind of appeal could trash not only the Conservatives’ reputation for economic competence, but also permanently brand them — in a country that is becoming ever more socially liberal and multiethnic — as the absolute opposite: a right-wing populist party that can’t win sufficient support from moderate floating voters.

Sound familiar? I’ll let you be the judge of that.