The Labour Party finds itself in a horrible place as parliament rises for the summer break. A dozen weeks since our overwhelming election defeat, Labour MPs are full of gallows humour and quiet despair – because, in choosing our new leader, we are making four of the same mistakes we made in 2010. First, like Gordon Brown after his defeat, Ed Miliband stood down as leader immediately. He hoped that the party could have “an open and honest debate about the right way forward, without constraint”. That debate has not materialised and we are having a family row with the Labour selectorate instead of a discussion with the British electorate.

Second, we are once again in a drawn-out leadership race that will exhaust the candidates, while David Cameron chillaxes on three summer holidays and Tim Farron and Nicola Sturgeon rally their troops for the battles ahead. Whoever is elected as leader will be drained by the campaign but have to start work right away. The first big test will be a speech to the trade union congress, which starts the day after the winner is announced on 12 September. The leader must then appoint a shadow cabinet, prepare for Prime Minister’s Questions, rebuild morale and write a cracker of a conference speech.

Third, we have a left-wing candidate on the ballot “for balance”. During the 2010 leadership election, David Miliband “lent” nominations to other candidates to ensure that Diane Abbott and Andy Burnham could take part. This made the transfers of voting under the single transferable vote system less predictable and, arguably, deprived David of the three or four extra MPs’ votes he needed to win. David’s legacy to Labour, which made it normal – Blairite, even – to put a left-winger on the ballot “to have a broad debate”, has dragged the leadership campaign to the left. Unfortunately, the electorate has moved to the centre right.

When I was still seeking MP nominations for the leadership, party members trolled me on Twitter, asking me to put Jeremy Corbyn on the ballot. I don’t believe in nominating someone I don’t intend to vote for. Corbyn’s presence on the ballot and his storming performances at hustings and in the constituency nominations have raised the prospect that he might win. That prospect, I’m sure, is as uncomfortable for him as it is alarming for the Parliamentary Labour Party.

Fourth, the centre ground remains a toxic place, with anyone who suggests that we listen to the public branded as a Blairite or a Tory, including, risibly, Harriet Harman. A colleague remarked to me, “You can blame Tony Blair for many things but you can’t blame him for winning three elections” – and, through those victories, lifting a million pensioners and a million children out of poverty, building a fairer workplace through the minimum wage and holiday entitlement, stopping mass murder in Sierra Leone and Kosovo, greening the economy and improving the lives of millions of people in the poorest countries of the world.

The public barely registers Labour’s leadership election, so rich in the narcissism of small differences. When we do make the news, people notice our internal divisions on the same issues that led them to reject us on 7 May: economic credibility, immigration, welfare. The challenges of technological change, housing and the migrant crisis in the Mediterranean are forgotten as the party debates whether Jeremy should have a seat in the shadow cabinet, or whether mothers make better leaders. People long for a centre-left party that speaks to the challenges of their lives, offers hope for their families and charts a course through choppy waters.

Significant international challenges lie ahead. As progressives, we must apply our values to shape Britain’s place in the world. Labour must resist the siren call of the left, which is busy learning the wrong lessons from Greece’s latest bailout. As the Labour MEP Richard Corbett points out, the Greeks had already had one long-term (30 years), low-interest (1.7 per cent) bailout from the IMF and the eurozone and the private sector had written off half of Greek debt. The Syriza/far-right coalition’s chaotic approach has led the Greek economy – which had returned to growth – to plunge back into recession, with the summer holiday period wiped out as tourists cancel their trips.

Yet those on the British left have branded the situation in Greece – Syriza’s referendum, capital controls and bank closures that have left crucial medical supplies running short – as a “coup” by Germany. They have started wondering whether Britain should stay in the EU, ignoring the social, economic, environmental and security gains that UK membership has brought us.

Labour is not yet in the place where we can say with confidence: “The only way is up.” Early findings from the “lessons learned” report commissioned by Harriet suggest that voters think that Labour simply does not understand their lives. We are in danger of becoming the political equivalent of Millwall Football Club. Their chant? “No one likes us, we don’t care.”

Andy Burnham has diagnosed one problem correctly – Labour has lost its emotional connection with the electorate. The solution is not to talk about rebuilding that connection but to do it. People vote not solely on the basis of which leader they would like to go down the pub with but on hard-headed calculations about which party is best for the economy and their family.

Yvette Cooper has rightly diagnosed that Cameron has a woman problem and she has a huge range of ministerial experience. Liz Kendall has told the uncomfortable truths that the party needs to hear. Both rightly talk about the need to campaign from the head and the heart. I am still undecided as to which woman I can see as a Labour prime minister in 2020, but I’ll be putting one of them at the top of my ballot as our best chance of winning.

Mary Creagh is the MP for Wakefield