ife under this government is a constant gear slippage between what you believe it to be capable of and what the external realities of the world demand. I have no confidence at all, for instance, in its ability to deliver a vaccination programme; all I can envisage is a vast contract delivered to some second-cousin-by-marriage of a minister, who reveals at the last moment that they don’t know how to keep anything refrigerated to -70C, but somehow that’s now the National Audit Office’s problem and they’ve walked off with the cash. And yet, simultaneously, a vaccination programme must happen. This great chasm between what’s imaginable and what is necessary for the government to do is nowhere plainer than with Brexit. Certain things must happen: Boris Johnson must decide whether or not to make a deal with the EU, and within the next six weeks. Neither rambunctious rhetoric nor anti-EU recrimination will mask the consequences of either outcome. The prime minister, last January, removed from the Withdrawal Agreement the section on parliament’s role in the negotiations, so he has the option to press ahead without a vote. However, the potential to embarrass the opposition by soliciting its view may be too good to pass up. In raw parliamentary terms, Labour MPs would be faced with a classic Solomonic dilemma: if they vote against any deal, and there are enough rebels on the Conservative side, they run the risk of actually precipitating a no-deal themselves. In the national interest, this would force them to vote for, or at least abstain on, more or less anything. Moreover, the extent of a Conservative rebellion, if indeed there were one, would not be clear until very close to the vote, leaving Labour unable to state its intentions plainly until it had a realistic read on the jeopardy involved. So in the worst-case scenario, Labour would remain evasive until the final hour, and then be accidental midwife to a chaotic no-deal finale. Meanwhile, if Labour MPs vote in favour of a deal, they make a mockery of the years spent opposing its flaws, and become complicit in any given negative outcome, which should be be laid squarely at the Tories’ door. If there’s one valuable lesson from Theresa May’s government, it’s that even the narrowest possible majority leaves very little room for an opposition to play in. Abstaining starts to look like the least-bad option, but that’s hardly safe: it was catastrophic for Labour to abstain on the Welfare Bill of 2015 – not because it could have effected a different outcome by opposing it, rather because it made the opposition seem spineless and calculating. The party’s fundamental values ended up being hollowed out by an unimaginative perception of what realism demanded. If the parliamentary strategy looks lose-lose, the optics are more hazardous still. Keir Starmer will be tempted to slough off his Mr Remain image – with staying in the EU off the table, there is absolutely no political capital in being that sober-headed, international-rules-based-system guy; indeed, it has long been a contradiction in terms to argue on rational grounds for a completely impossible outcome. The most successful attacks the Conservatives have so far made on Starmer – or at least, the attacks they find most satisfying, given how pleased they seem to be to repeat them – centre on the idea that he rejected and continues to reject the referendum result, and therefore has no respect for democracy. Add to that the opposition’s red-wall fixation, and early bids to retake those traditionally Labour, socially conservative heartlands with talk of patriotism, and the situation appears to call for a Labour leader who has at least fully accepted the necessity of leaving the EU, even if he will never love it. However, there is an important counterpoint: far more pressing for Labour’s electoral recovery is that people can see who the leader is, and can see that his words and actions reflect a value system that is solid, consistent and true. If universal human rights have been the lodestar of his career, the connective tissue that draws together the professional, political and personal, they cannot be shunted to the margins because Priti Patel portrays them as elitist or a focus group finds them boring. They must inform the party’s response, on everything from freedom of movement to the Good Friday Agreement. Likewise economic justice, environmentalism, peace and international cooperation. These are more than strategic priorities: they are the pillars of the progressive political self, and there are very few issues raised by the Brexit process, from the foreseeable impact on trade, agriculture and manufacturing, to the more perverse consequences for the hedgerows of Kent, that do not touch on them. The success of the Brexit project has been to collapse all ideological complexity into one question; the opposition will start to succeed when it disaggregates the issues so that they once again have meaning, and points to a plan. While the party should remain stalwart on its own values, it has to adapt to changing external realities. The public may have voted to “get Brexit done” nearly a year ago, but that hasn’t translated into broad support for the idea, which as of last week was opposed in a poll by 49% of respondents (41% still in favour). It is possible to think something’s a terrible idea and simultaneously want to stop talking about it, as anyone who’s ever been in a relationship knows. For Labour to vote in favour of a deal with the EU as negotiated by Johnson would be to chase yesterday’s polls, and accept the Conservatives’ version of authenticity, which is corrosive to its own. If it abstains, it makes itself irrelevant – not just in the moment, but in any future critique. There is no clever answer to a future vote on a Brexit deal, but that is perversely liberating. When you can’t be clever, all you can be is truthful. The honest course would be to vote against the government. Zoe Williams is a Guardian columnist