In an era in which real pay rises had become a thing of the past, except for the propertied classes, it should have come as no surprise that centrism was eroding as a political force and that alternatives were starting to flourish.

Labour has always been a party with democratic socialists in it, but the number of socialist members from 2010 onwards were beginning to swell. This change was visible on a number of fronts. In the NEC elections, the Left’s performance incrementally improved in each vote during the parliament. In 2012, Ann Black and Ken Livingstone both on the left slate topped the ballot, with Livingstone achieving 26% more of the vote than the most successful candidate from the right of the party.

In 2014, the Left won the majority of the six elected places with a similarly sized lead. Left Futures, the blog associated with Jon Lansman, responded to the results by cheering on the ‘best Left result since 1980s’. Pete Willsman a left-winger and prominent member of the Campaign for Labour Party Democracy narrowly lost out to winning a seat, depriving the Left of a fifth seat out of the six.

The pre-2015 composition of the party membership looked to still be tilted toward the Left, despite claims to the contrary by many people within the commentariat. Notably the most successful candidate to be backed by the right of the party in 2014’s NEC election was Ellie Reeves who was also arguably the member of the slate least associated with New Labour. Centrism was on the wane.

In practice there was little to be surprised about. Occupy, the People’s Assembly and UK Uncut all offered a political direction to many young activists and were forging links with organised labour, all within a climate in which the economic orthodoxy was strangling people’s wages.

Though moderate by many measures, Miliband was elected leader with commitments to a real living wage, scrapping tuition fees and progressive taxation. This is not a defence of the party’s repeated mistakes in the 2010-15 parliament, which included the partial acceptance of Tory reforms to the NHS, backing for ‘austerity-lite’ and a failure to grasp the depths of the crisis. But it is an acknowledgement that the seeds of the socialist-tinged programme of the 2017 Manifesto had been growing among Labour’s grassroots ever since Labour last left office.

Miliband broke with New Labour on foreign policy (Iraq), on education (tuition fees, academies) on taxes (the mansion tax) and on state intervention (the City, energy). The new leader emphasised that the Iraq War was a failure and a mistake. He first rejected tuition fees with a call for them to be scrapped, but ultimately backed down. Miliband raised the prospects of a form of wealth taxation, incarnated as a ‘mansion tax’, to take on Britain’s towering inequalities and better fund the health service. Miliband also identifies the dominance of the big six energy corporations and of the big banks as a source of considerable discontent. Here Labour began to advocate a ‘breaking up’ of the big banks (dividing retail and investment banking) and a degree of restructuring the energy companies, combined with the infamous energy price cap. … For the most part neither socialistic nor New Labourite in inspiration …

The various breaks with New Labour were incremental but were noticed by the wider electorate – and it was here that the Labour right could plausibly link perceptions of Miliband to Labour’s failure to win. In 2015 it was found that voters perceived Miliband as being distinctively to the left of both New Labour and the Liberal Democrats. The reality was that it wasn’t the shift leftwards, but instead Miliband’s failure to clearly set out his agenda which lost Labour seats 3 years ago.

The party itself repeatedly veered toward the centre on issues where the public and the activist left were at one. Though the party and the public have consistently supported public ownership of the railways, Miliband as leader faced a battle over whether to return all of the railways into public ownership or simply to reiterate Labour’s 2010 policy. The 2010 pledge consisted of a plan to allow the public sector to bid for the right to run individual rail lines but would have left many lines in the hands of private companies. This wasn’t the exception, it was the rule.

The failure to adopt the policy saw Labour’s grassroots applying pressure on the leadership and a wave of prospective candidates calling for re-nationalisation, among them were Cat Smith, Nancy Platts, Wes Streeting and Clive Lewis. Fearful of being portrayed as offering a return to the days of British Rail and Old Labour, Miliband, or at least those around him in the Shadow Cabinet, resisted the calls for public ownership from Labour’s rank and file and many who are now Labour MPs.

In 2012 the Labour Party conference was met with a flurry of motions stridently repudiating the coalition government’s NHS reforms, but these motions went further than either Labour’s 2015 pledges drawn up by Andy Burnham and the most recent manifesto pledge. The motions called for the active reversal of the privatisation and marketisation of the NHS, including the Blair era reforms which expanded competition between hospitals and expanded the presence of private companies in providing healthcare.

Just a year later, party conference voted unanimously to return Royal Mail and the railways into public ownership – a decision which the Parliamentary Labour Party was immediately keen to distance itself from, despite both proposals being expressly what the public wanted.

In the party’s youth wing, the changing mood went beyond a move in the direction of conventional social democracy and demanded more radical change. In 2014 Young Labour voted to adopt a policy of advocating for a stringent wealth tax, ending the right to buy, introducing free public transport for jobseekers and putting workers on boards. Something akin to the Corbyn surge was no doubt already taking place.

None of these changes in the party and it’s youth wing’s official stances were reflected adequately, or in some cases at all in the final 2015 manifesto. The final document, entitled ‘Britain Can Be Better’, was loaded with amiable, progressive policies but was also characterised by the glaring absence of the policies decided by party conference – alongside those Miliband had championed at the beginning. Jon Cruddas, the Chair of Labour’s Policy Review, has since claimed that the manifesto was re-written after the Clause V meeting – the official meeting in which the party voted on its content.

Labour entered the 2015 election with a disconnect between the manifesto and the party’s stances as decided by conference. Here there was a strong parallel with 1987 when the same happened. Margaret Thatcher declared that Labour was standing on an ‘iceberg manifesto’ concealing a hidden, hard-left agenda. Yet David Cameron did not opt to follow that line of attack, perhaps because after all Labour had been ignoring democratic decisions made at conference for around two decades. The open, decentralist method of debating and adopting policies seemed to be a relic of a bygone era. No wonder the Labour Party’s grassroots now feel listened to for the first time in years.

Yet in the five years prior to Labour’s 2015 defeat there were repeated signs that the changes in the grassroots were slowly percolating up to the leadership – the problem was that the change of pace was too slow. The existential crisis of British politics required a little more than incrementalism.

The changing face of the party did become visible at several crucial points. Firstly in Ed Miliband’s decision to oppose throwing Britain into a war in Syria in 2013. This was the first sign of a break with an unpopular consensus at the top of the party which didn’t just go back to New Labour but to Neil Kinnock’s decision to back the Gulf War more than 25 years ago. Liberal (military) interventionists of all parties denounced Labour’s position but it was the party’s hesitancy, rather than the position itself which failed to galvanise the electorate.

Whether or not this was an example of foresight, there is a strong case that the decision prevented the UK from becoming embroiled in a conflict in which substantial numbers of our allies in the FSA (Free Syrian Army) went on to defect to militant groups. In 2013-14 large numbers of the FSA defected to the militant Islamist group Al-Nusra, the Al-Qaeda splinter group which seeks to establish its own Islamic state.

After the Gaza War the following year, the party responded by backing a motion in parliament to officially recognise the state of Palestine. The motion passed (but has yet to be formally implemented) and has served as a template internationally in asserting the right to self-determination. Three years later the resolution was enshrined in both the draft and the final copy of the party manifesto.

2015 was the first time in my lifetime that Labour’s ran on a platform of explicitly calling for a democratic, wholly elected House of Lords – perhaps more Tony Benn than Tony Blair. The proposal for an elected ‘Senate of the Nations and Regions’ was among the most thought out and fleshed out proposals for replacing the Lords ever put forward by a political party, and it came with the possibility of the new chamber sitting outside London . This was a reflection of the desire to cut the rot out of British politics and to develop tangible reforms to make British politics less Westminster-centric.

Some of this change within the party would not have been possible without the arrival of a new cohort of working class left-wingers. A less top-down approach to selecting candidates inevitably led to members choosing local candidates far more in line with their own views. Had this not happened it is likely that only three candidates would have made it onto the ballot in 2015 – and Jeremy Corbyn would not have been one of them.

The doctrines of Selsdon Park, Thatcherism and the New Right are ceasing to be the order of the day, or at least ceasing to be palatable in contemporary discourse. Conservative backbenchers now speak approvingly of employee-ownership and co-operatives, both forms of social ownership – though there have been no examples of right-of-centre MPs offering meaningful proposals to strengthen the hand of working people. Sustained hits to the living standards of the majority, while wealth bubbles up to the richest few, have opened up the possibility of political alternatives – and the Tories are losing on the battlefield of ideas.