In the months leading up to May’s general election, pundits claimed we were entering a new era of multi-party politics. In the end, it came to nothing. Though the public is still less willing to vote exclusively for the two main parties, with the exception of the Scottish National Party the political challengers are still grossly under-represented in our democratic system. We are stuck with first-past-the-post, which will continue to favour the Conservatives.

The problem for non-Conservatives is still, as it has always been, to create a single, moderate, electable progressive party able to appeal to the left-leaning half of the electorate. For most of the last century, that was what Labour aspired to be. Yet, despite their devastating performance in May, this is what the Liberal Democrats have a better claim to today.

Labour was founded in 1900 as an uneasy coalition of two distinct strands, the trade unions on the one hand and socialism on the other. But from the 1920s to the 1970s, the numbers, muscle and money of the unions created a powerful election-winning machine (with two high peaks in 1945 and 1966) which went a long way towards achieving a more equal society. After the electorally suicidal lurch to the far left after 1979, Neil Kinnock, John Smith and Tony Blair managed to rebuild a party capable of winning again in 1997 – but they did so only by abjuring socialism and progressively weakening the link with the unions.

The two traditions which historically supported Labour are both exhausted. Today, the unions represent only a minority of the workforce concentrated in the dwindling public sector. Meanwhile, belief in socialism as traditionally understood from Attlee to Wilson – nationalisation and economic planning, universal public services supported by redistributive taxation – is almost totally discredited and forgotten. The surge in support for Jeremy Corbyn which so embarrasses the mainstream candidates has revealed a deep hankering among party members to take Labour back to its socialist roots. Shorn of socialism and no longer the army of the organised working class, Labour post-Blair no longer knows what it is for.

The rise and decline of the Labour Party coincided almost exactly with the start and end of the 20th century; its historical mission is now played out. The Liberal Democrats, on the other hand, are now the inheritors of a Liberal tradition going back to Gladstone which is still as relevant as ever, and consists of four distinctive strands: constitutional reform (which in modern terms means electoral reform, reform of the House of Lords, and devolution); civil liberties (that is, individual liberty, free speech and minority rights); anti-imperialism (leading to suspicion of foreign wars); and improving the condition of the people (reducing poverty, promoting greater equality and social mobility). To these historical goals can be added two more recent concerns: commitment to Britain’s place in Europe and a determination to tackle climate change.

Labour leadership: The Contenders Show all 4 1 /4 Labour leadership: The Contenders Labour leadership: The Contenders Jeremy Corbyn Jeremy Corbyn started off as the rank outsider in the race to replace Ed Miliband and admitted he was only standing to ensure the left of the party was given a voice in the contest. But the Islington North MP, who first entered Parliament in 1983, is now the firm favourite to be elected Labour leader on September 12 after a surge in left-wing supporters signing up for a vote. PA Labour leadership: The Contenders Liz Kendall Liz Kendall has been labelled the Blairite candidate throughout the contest, which partly explains why she has failed to attract the support needed in a party that has drifted even further from the centre-ground of British politics since the election. She has faced criticism over her relative lack of experience, having only served as an MP since 2010 and having no experience of ministerial or shadow cabinet roles. But that very lack of experience allowed her to initially make a pitch as the only candidate offering real change and a real break from the Blair/Brown/Miliband years, until Jeremy Corbyn entered the race and shifted the whole debate to the left. She is set to finish a disappointing fourth. PA Labour leadership: The Contenders Andy Burnham Andy Burnham started out as the front-runner in the leadership election, seen as the candidate of the left until Jeremy Corbyn entered the race. The former Cabinet minister has found himself squeezed between the growing populism of Corbyn’s radical agenda and the moderate, centre-left Yvette Cooper, not knowing which way to turn. It has attracted damaging labels such as ‘flip-flop Andy’, most notably over his response to the Government’s Welfare Bill. He remains hopeful he can win enough second preference votes to take him over the 50 per cent threshold ahead of Corbyn. PA Labour leadership: The Contenders Yvette Cooper.jpg Yvette Cooper has put her experience and achievements in government at the heart of her offer to the Labour party. She played a key part in setting up Sure Start in Tony Blair’s government and has pledged to continue her record on delivering for young families by promising a “revolution in the way families are supported” by introducing universal free childcare. She has also championed her role as a full-time working mother, taking pride in telling audiences that she does the school run for the kids before her day starts as a politician. But she has been criticised for being too wooden and lacking in passion and her attacks on Liz Kendall for “swallowing the Tory manifesto” at the start of the leadership contest have been criticised for helping Jeremy Corbyn brand all three mainstream candidates as ‘Tory-lite’. PA

Historically, Labour has never been very interested in constitutional reform or minority rights; its record on Europe and the environment is patchy at best, and Iraq fatally damaged its anti-war credentials. Meanwhile, its efforts at abolishing poverty and improving the lot of working people – its real raison d’être – have had only limited success.

Socialism proved to be a less efficient creator of wealth than the free market, so that from Macmillan to Thatcher the Tories consistently won the economic argument; but Thatcherism has brought only greater inequality and social injustice. Inequality remains the most urgent problem needing to be addressed today; but it is one to which Labour has no exclusive answer.

The two central achievements that Labour harks back to as representing the implementation of its values in practice – the NHS and the welfare state, and full employment maintained by a mixed and managed economy – were actually the achievement of two paid-up Liberals, Beveridge and Keynes, building on the foundations laid by the Liberal government of Asquith and Lloyd George before 1914.