How did we get here? It is a question that demands an answer, because Brexit has dominated Britain’s political debate for the past three years—and will do so for many more. The vagueness about what Brexit means has created a new political fissure that seems unbridgeable.

Read: Even now, Brexit remains impossible to understand

From the start, soon after the referendum result was announced, political logic bent the outcome toward a hard exit. What evidence could be flourished at voters to show that the government had accomplished Brexit, beyond symbolic moves such as changing the color of Britain’s passports back to blue, their color before the country joined the EU? Trade deals “were honed in as something that could be held up as a trophy,” Sam Lowe, a senior research fellow at the Centre for European Reform, a London-based think tank, told me. To strike trade deals, Britain needed to leave the regulatory and customs orbit of the EU—being a member means you give up the right to negotiate your own tariffs. And if some distance from Europe was liberating, wouldn’t going further be even better? In politics, it is hard to argue for half-measures.

Since then, events have followed a predictable pattern. Every potential form of Brexit has been denounced by the most vocal Leavers as insufficiently hard. The logical conclusion is that only the most disruptive form will do. To many Brexit voters, no deal sounds alluringly like a complete break, but it is a misnomer, because a chaotic exit would undoubtedly be followed by a series of deals to allow planes to fly and supply chains to function.

For an example of a politician whose Brexit position has hardened, look no further than Prime Minister Boris Johnson. As late as March 2016, three months before the referendum, he refused to answer directly whether he wanted Britain to leave the single market, the system by which goods and people flow without restriction within the EU, saying only that the country would have “our own British arrangements.” By July 2018, he had resigned as foreign secretary because he could not support Theresa May’s deal, even though it would see Britain leave the single market and customs union; he has dismissed it as merely a “semi-Brexit.” As recently as yesterday, he said Britain “cannot accept the current withdrawal agreement.” That deal, which would once have been considered a hard Brexit, has been referred to as “Brino”—Brexit in name only—by the Conservative lawmaker Jacob Rees-Mogg, echoing descriptions of moderate conservatives in the United States as “Republicans in name only.”

Read: Boris Johnson’s plan to solve Brexit: Believe harder

The disappearance of the Brexit middle ground should be a sobering and educational experience. If Britain ever again decides to settle a constitutional question with a referendum, the vote should be run very differently. To avoid years of bitterness and delay, the government must support the proposed change, rather than the status quo—thereby heading off questions of commitment to the result, as has been the case here—and produce something close to a manifesto for what that change should look like.