This article was originally published in today’s edition of the i paper.

I deeply dislike Theresa May’s Withdrawal Agreement. It doesn’t fulfil her promises, it doesn’t maximise the opportunities of Brexit, and it doesn’t fully free our country from the undemocratic EU. On her own terms, it is a bad deal.

But we have reached a point at which MPs ought to vote for it. The value of the proposal has not improved – no legalese figleaf or empty verbal assurance makes it any better. Rather, the alternative to it has changed.

The negotiating logic that No Deal is better than a bad deal still stands. I would support a No Deal Brexit if one was on offer, as we were promised. But it no longer is.

Exit without a deal on 29 March remains the legal default. The rules and conventions of our democracy – as well as May’s very clear promise – should make that almost impossible to change. But politicians accustomed to getting their way have decided to get what they want at any cost.

The Speaker disgraces his office by ignoring his responsibility to be impartial. The House of Lords overreaches its constitutional role to meddle in the purpose of legislation. Cabinet ministers abandon collective responsibility. All these are outrageous offences: powerful people prioritising their desires above the rules and reputation of our democracy.

But while it is disgraceful, it has still happened. Despite the severe cost to Parliament, enough politicians have behaved dishonourably that they are about to get what they want. The choice facing us – for now, at least – has changed from “deal or no deal” to “deal or no Brexit”.

All the high-minded principles they cited – accountability, compromise, deeper scrutiny of the terms of exit – were a lie in the service of Remain. The latest falsehood is that a delay without a deal is simply time to work on the details. It isn’t, it’s a deliberate effort to try to obstruct the very possibility of fulfilling the referendum result.

That presents Eurosceptics with a choice – the same choice we faced through four decades of campaigning for democratic self-government. We can be pure, regardless of circumstance, and lose, hoping to warm ourselves in defeat with the cold comfort that we went down fighting. Or we can be pragmatic, take what limited victory is available, and fight on for the eventual goal.

The temptation to go out in a self-indulgent blaze of glory is strong. But this is a test of principle. Is our cause truly about escaping the EU, as we say, or is it about imagining a heroic myth about ourselves? Do we want to win, or spend our lives moaning about how we could have won?

I wish we were leaving the EU properly and promptly. I wish politicians kept their promises. But we must deal with what is real.

Though I would like to be able to hang up my sword, 13 years after co-founding the Better Off Out campaign with the support of just one MP, that evidently will not be allowed. Forced to choose between fighting to get us out of a bad deal, but from outside the EU, or restarting the 40-year battle to leave from scratch, I opt for the former.

After the shameful performance of so many MPs, I expect that if we stay in they will do stop at nothing to lock us in forever. The cost – economic and democratic – would be vast.

Some people will be aggrieved by my choice. I feel that way about having to make it. Eurosceptics should exact a price for being forced into such a corner.

Those who made this happen – the Prime Minister, as well as those Cabinet ministers and MPs who promised one thing then did another – should be turfed out. The Speakership should be given to someone who values it. Eurosceptics must harshly scrutinise our own errors which allowed us to be outmanoeuvred.

And the campaign to escape the deal should begin on day one.