Party loyalty is a thing of the past, writes Alan Taylor , while Peter Muchlinski says that the political future requires replacing the residual elements of the ‘growth society’, with the ‘sustainable society’. Plus letters from Andrew Graystone and William Wallace

So, Boris Johnson fears that the Conservatives may face extinction if they delay Brexit (Report, 5 June). He may be right, on this at least, but for the wrong reasons. The fact is that the decline of the Conservatives, and of Labour, is a long-term process which began 60 years ago and may only now have reached its culmination. Both main parties have underestimated the consequences of this decline. The result is that the transformation in party voting seen in the Euro elections and since may be permanent.

British politics has long been seen as dominated by two big parties, each with a block of loyal supporters, and a small number of “floating” voters between them. This was an accurate picture of elections in the early 1950s, when over 80% of the electorate voted Labour or Tory. But this two-party domination began to weaken from the late 50s, a trend that has continued ever since. Turnout fell as fewer people were enthused by the main parties. The growth of this pool of unattached electors gave space for Liberal and Liberal/SDP “revivals”, the growth of nationalist parties in Scotland and Wales, and now the rise of the Green party and the Ukip/Farage phenomenon.

The decay of two-party domination had been obscured by the first-past-the-post voting system, with changes in voting not fully reflected in parliament. Certainly, the fall in turnout, and in electoral registration, had no apparent political impact. But most people are no longer loyal Labour or Tory voters. The traditional sources of loyalty to these two parties, based partly on social class, are now not the main motivation in voting.

The referendum revealed a new and passionate division between two broadly equal-sized parts of the electorate. This cleavage is based on real divisions of interest and between sets of values. The intensity of the feelings on both sides has pushed the remnants of former loyalties aside, and this change is probably permanent. Neither Labour nor the Conservative party is unambiguously identified with one or other side of this new fundamental cleavage in British political opinion. As a result they may both finish up in the often-cited dustbin of history.

Alan Taylor

London

• Coverage of the EU parliamentary elections, and Andy Beckett’s essay (Conservatism in crisis, 28 May), show that the main political parties cannot develop the new politics needed for the long-term issues we face. Modern conservatism and social democracy/socialism arise from the class struggles characterising late 19th- and 20th-century mass industrial society. The core question was how to distribute wealth through variations in property ownership and rights. The growth-based economic model, within which that debate was centred, is being overtaken by the reality of climate emergency.

This involves a completely new mindset and culture. The political future requires replacing the residual elements of the “growth society”, with its emphasis on consumption – whether individual or collective – and the freedom to do so, with the “sustainable society”, a post-consumerist society where social justice hangs on the ability of society to preserve the environment and harness technology to this overarching aim. Social democracy/socialism has to ditch its obsession with industrial growth and contribute its traditional emphasis on social justice. It must add itself to the green movement.

Part of the process of getting there requires, sadly, a preliminary conflict between the emerging green movement and the reactionary last gasps of conservatism, displayed by nationalist populist parties, whose chief characteristic is to act as a brake on social change often accompanied by climate emergency denial. They are on the losing aside, even if it may not seem so today. Their children and grandchildren will see to that.

Peter Muchlinski

Emeritus professor of law, Soas University of London

• I was a Change UK candidate in the European elections. Like my 70 colleagues I invested time, energy and reputation in trying to create a credible alternative to the old political parties. We brought experience from the public, private and voluntary sectors. We pitched in because we hoped we could create a different way of doing politics, with an emphasis on collaboration, listening and inclusion – qualities that have been mislaid by the existing parties. No one believed the job would be done and dusted on 23 May.

In the fortnight since the election, Change UK candidates and supporters in the regions have been buzzing with energy and ideas for how to do things differently. It is extremely disappointing that the rug has been pulled from under us by a small group of MPs in London (Change UK loses six of its 11 MPs as woeful EU election result takes toll, 5 June). We had hoped the Independent Group might be the catalyst for gathering people with knowledge and experience to offer. Instead, more than half of the Change UK MPs have walked away without consulting us. The problems that led many of us to leave our existing parties remain unsolved. Change UK or not, the renewal of politics is not going to come from Westminster, but from fresh local and regional initiatives. Otherwise, plus ça change, plus c’est la même chose.

Andrew Graystone

Manchester

• Good of you to give your readers a two-page spread on the Conservative leadership race (4 June), after the extensive coverage of Labour’s internal struggles and debates in recent weeks. But a high proportion – quite possibly a majority – of your readers voted Liberal Democrat or Green in the Euro elections. Should the Guardian not respond by covering these two parties – their policies, leadership elections and internal debates – a little more frequently?

William Wallace

Liberal Democrat, House of Lords

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