Though we don’t always admit it, lots of us pro-Europeans have spent the years since the Brexit referendum trying to juggle two essentially irreconcilable views of what should happen next. One is that, awful though Brexit is, the leave vote must be honoured in the least damaging way. The other is that Britain’s departure from the European Union is so mistaken that it must be reversed, once again with least damage.

More than three years on some of us are still juggling, even as Boris Johnson heads to Brussels. The thing that keeps the juggling alive is not, in the end, an inability to make up our minds. I am a remainer. Full stop. The question is how to respond to Brexit in the political circumstances of the moment, in the best long-term interests of the country as a whole? The answer has evolved. But it will soon be make-our-minds-up time.

Back in 2016 my response to the leave victory was to lament it bitterly but to say that Britain should continue to hug Europe as close as possible, even while leaving. This would help to protect jobs, secure the Irish peace process, and allow Scotland’s remain vote to be treated with enough respect to avoid Brexit becoming a threat to the union. A decade or so down the line, my rationale went, it might then be possible to reopen the question of EU membership, especially if the EU had continued to evolve in a multispeed manner, and if post-Jeremy Corbyn Labour had got off the fence to support Britain’s place in Europe.

Instead, the longer that process has gone on, the wider the gap has grown between the original democratic deference owed to the idea of “leaving” in 2016 and the real-world consequences of the detailed version on offer in 2019. Simultaneously, however, the passage of time has made no difference at all to one very big thing: the concern among many leave voters that what they wanted in 2016 has still not happened. To reconcile these two realities is almost impossible, because it pits the malleable pragmatism of representative government against the rigid mandate of government by populist referendum.

As the process has lengthened, so the options have widened. This isn’t the conspiracy that some claim to see. It is simply the entropy of politics at work. Few talked about a second referendum back in 2016. But the issue is central to the debate now. Almost no one in 2016, certainly not Johnson, imagined the UK leaving the EU with no deal at all. Today, despite the ongoing talks, no deal is a Johnson government policy option. In the immediate aftermath of the Brexit vote, reversing the 2016 result had few supporters. Today it is the policy of the Liberal Democrats and the SNP and both are prospering in the polls.

There is no perfect choice to be made on Brexit. The fault with that lies in the way the referendum process was devised – verdict first, terms later. All the options come with risks, often very big ones. But we don’t solve anything by wishing we could have made better choices at previous turnings along the way. The here and now choice takes two forms. The first is between Johnson’s deal, no deal and remaining in the EU. The other, which applies as much to hardline leavers as it does to remainers, is between folding and fighting on.

The case for Johnson’s deal is that it means Britain leaves the EU in line with the referendum vote. That’s not a minor civic consideration. People are weary and angry. A deal could draw some of the worst poison from public attitudes to politics. It would satisfy the many (more than some of us want to think) who just want the whole thing over, although in reality almost everything about Britain’s future relationship with the EU is still to be decided. It might, if you agree with Corbyn, allow a general election to be fought on “real”, that is to say domestic, economic and social issues.

But it would still be a terrible deal and that can’t be ignored, however weary we are. It would mean buying a pig in a poke and hoping that what’s inside entails a good future for the British people. It would defer rather than solve the Irish border crisis. It would risk breaking up the union. It would instantly worsen the UK’s trading position, with severe short- and long-term impacts on the economy and jobs. It would weaken the UK in the negotiations during the transition period. And it would set Britain at odds with its only true geographic and regional allies.

The lesson of the past three years needs to be faced. That lesson is not that politicians are out of touch or failing to listen. It is the opposite. It’s not that the country can get along with Brexit. It is the opposite of that too. The lesson is that Brexit won’t work.

Brexit won the vote. But it’s an ideology not a policy. When its supporters tried to turn it into policies, as they are still trying to do, it fell apart. It made things worse. These three years have been the leavers’ fault and no one else’s. That’s why obstructing no deal has been so important.

But it’s also why preventing Johnson’s deal is important too. Optimism and slapdash policy will not make Britain a global power. Theresa May was right when she said Brexit means Brexit. That’s exactly what’s wrong with it. It’s why, in the end, Britain has to do everything possible to retain its place in Europe, in spite of the difficulties, and persuade its people in a new campaign – not with a message of fear, but with a message that pro-Europeans are listening to what’s wrong with the country.

It certainly will not be easy. Most battles are not fought on ground of one’s own choosing. But as long as the passage of time and the sheer folly of Brexit permit the possibility of remaining, Britain should make up its mind to remain.

• Martin Kettle is a Guardian columnist