The surprise Conservative victory over Labour in July’s Uxbridge and South Ruislip byelection did not shift the national opinion polls. But Uxbridge was a pivotal event nevertheless. It delivered an enduring warning about the way modern politicians approach environmental change. It highlighted some of the very real political hazards facing those – in this case the London mayor, Sadiq Khan – committed to otherwise popular policies for which, it now turns out, the ground has not been adequately prepared. In some respects, Khan was simply unlucky. Without the byelection in Boris Johnson’s former seat, Khan’s plan to extend his ultra-low emission zone to outer London might have come into force this week with relatively little fuss. Yes, there would have been some grumbles and protests but, at most, the Ulez expansion would have led the regional bulletins, not the national news. Instead, the Ulez-dominated byelection campaign has sent a bolt of electricity through both main national parties. Tories who never bought into the green agenda now feel liberated to extend the attack on to a broader front. Rishi Sunak, clutching at any straw, toys with doing the same. Labour, meanwhile, is suddenly more wary about its earlier green promises. Electorally, all this may get another outing among car users in the rural Mid Bedfordshire byelection, as well as in south-east England’s marginal seats in the general election, and in Khan’s re-election contest next May. But all this highlights a much wider problem, which goes well beyond even saving lives and the environment. This hesitant, stop-start-stop political culture exposes a systemic problem about the way British government works – or, rather, doesn’t. The overwhelming majority of Britons, in every part of the country, want cleaner air. Only a minority are in denial or don’t care. In principle, people support action, provided the measures seem sensible, appropriate and fair, and that adequate preparation is made for the transition. It is clear this did not happen over the extension of Ulez. The upshot is that measures that would and could have secured sustained public backing, as well as being of public benefit, have become needlessly contested and at risk of being derailed. That failure is the result of our political system. British politics needs to find ways of driving significant changes that are much more resilient to political buffeting of this kind. The structural problem is how to steer a course towards implementing things on which there is general agreement, and are within our power to do. Controversy over cleaner air is merely one example. Achieving net zero emissions may now be vulnerable in the same way. There are dozens of others. Rebuilding the National Health Service is probably close to the top of many lists. Creating a national social care system that works can’t be far behind. Other big ones might include making the police service more effective, and building better relationships with Europe. In principle, the list is endless. In all these cases, there is a substantial public majority, in some cases an overwhelming one, for action. In most cases, polls confirm there is also a considerable measure of agreement about some of the details and limits, and the values in play. The public seem open to the case for change, if increasingly resigned to it not happening as well or as soon as it should. The public mood appears to echo the consensual readiness to make reasonable sacrifices that was evident in the pandemic. Britain needs to tap into this benign national feeling. Yet Britain always struggles to construct the bridge linking public readiness and achieved outcomes. Populist and partisan politics have made bridge-building less attractive and more difficult. Social media have increased the instability. In the more deferential past, the bridges would have been constructed after a royal commission consisting of the expert and the eminent. But modern politics, with its desperate compulsion to retain control, recoils from such exercises. Are we doomed to have the same arguments year after year without settling on solutions to issues such as net zero and the NHS? It may be that modern politics is incapable of addressing the long term. The parties currently struggle to find ways of agreeing on national projects that may take 10, 20 or 30 years to reach fruition – and then to stick with them, making adaptations as they become necessary. The solution is not to scrap the democratic system but to adapt it. The answer does not lie at the top, with better leaders than in the recent past, although that would help. Urging the political parties to trust one another more won’t cut it, although that too would assist. Changing the electoral system would not achieve the necessary policy stability either. Nor is the answer to be found, as some seem far too content to say, by electing a Labour government that will magically solve all the problems. Even passing legislation to embed long-termism in our politics would not do the trick, because it is largely performative and can be undone. Some institutional changes might help, such as an office of environmental responsibility to crack the whip over successive governments. Better media would certainly assist too. In the end, the best hope lies with the people, not the politicians. Not for the first time, modern Ireland seems to offer a way forward from which Britain can learn. Ireland has for some years developed a system of deliberative democracy. In this system, a demographically and politically representative sample of up to a hundred voters, sometimes dubbed a citizens’ assembly, commits to examine the issues and listen to submissions, before attempting to write a policy agenda that all, or most, can endorse. The aim is not just to improve Ireland’s laws, but to help embed the conclusions more firmly in a broad coalition of support by making recommendations about related policies and service implications. The process necessarily involves discussion, compromise and shared political ownership. And it can work. At its best, it can overcome entrenched opposition and overcome years of deadlock. The Irish process did this spectacularly in laying the groundwork for the abortion referendum in 2018. It is currently attempting to do the same over drugs laws and strategies, an issue that Ireland, Northern Ireland, England, Scotland and Wales have all found intractable over decades and on which they could all usefully adopt common approaches. The next meeting of the Irish citizens’ assembly takes place this weekend. Would such a strategy work in Britain, where politics and government have become so encrusted? Why should it not? Deliberative democracy won’t solve every problem, but it would certainly open up the possibility in a much more positive way than at present. After Uxbridge, we surely need to try something different, and something that works. Martin Kettle is a Guardian columnist