Anyone standing for leader of the Labour party has a responsibility to speak truth, because without that we will never win power. We cannot spend the next few months playing to the crowd or making excuses. Nor can we lay all the blame at the feet of Jeremy Corbyn. Our problems have been growing for years. Our job is to show that we understand why so many voters lost faith in us and, crucially, that we care enough about their lives to win them back.

The Labour party has always been an at times uneasy coalition of those for whom socialism is an intellectual and moral commitment and those who saw a Labour government as a vehicle for protection, whose support was based on self-interest rather than a deeper political theory of society. That relationship was forged through nonconformist churches, temperance societies, the trade unions, the provision of council housing. These institutions gave people a sense of shared interest. Many still exist, but, if we’re honest, they’re a shadow of what they once were.

The huge brick-built works that brought people together have been replaced by a thousand cold glass business parks. The car factory that employed, in some way or another, everyone in my family is now an M&S and Sainsbury’s. Unions have arrested decades of decline but the proportion of people who are members is at its lowest ever level.

Today we’re more distanced from each other, the bonds formed at the local shop replaced by the massive supermarket or the stressed driver thrusting a package through a letterbox. Instead of meeting in pubs, more of us sit at home with supermarket wine and Netflix. Social media keeps us in a bubble, away from people who might challenge our prejudices.

For all of my life, Labour has struggled to find a real answer to the erosion of the things that grounded our party and brought us together. In the 1990s, the answer was to modernise and professionalise our party. It worked to a point. Then Gordon Brown tried to introduce the concept of “progressive patriotism” to forge solidarity between different parts of the party. Ed Miliband flirted with community organising. In the past few years we’ve hoped that the return of ideology in politics, after the financial crisis, would turn the tanker around. While we’re intellectually more confident, it clearly wasn’t enough to overcome these trends.

I’m not so arrogant that I believe my personality alone will transform our fortunes

Any candidate who pretends they have a simple solution to these fundamental issues is kidding themselves. Rather than reach for trendy ideas, we need strategy. We need to revamp our campaigning so we reach the whole country, rather than building up huge majorities in some seats while losing others. We need to tell a story about our country that connects us to people; to win good faith by being more active in our communities; and we need to be confident to speak for what we believe in, never being neutral on the hardest questions.

At the election we jumped from policy to policy so quickly that people didn’t believe the specifics. They were left with a sense that we were promising the moon. The bitter irony is that it was the scale of the change we were offering that made it harder for people to have hope.

The economic insecurity and Tory cuts of the past decade haven’t just increased poverty, they have increased despair. We used to just expect our children’s life chances would be better than ours. If anything I expect life to be harder. Harder to buy a home, harder to access training, harder to get a job. For a party of the left to win, people have to have believe that government, the state, can be on their side. When I was a young mother, Sure Start and tax credits weren’t just a financial lifeline, they represented hope. They were proof that someone cared enough to do something. When did someone last experience that?

Creating hope from opposition won’t be easy, but we can start by using the leadership election to renew our moral purpose. That means speaking a language that demonstrates we see the world as ordinary people do and we share their anger at the things they see that are wrong.

For me socialism has never been an intellectual pursuit. It comes from my upbringing and experience. The stories retold in my family were of my mum chasing a racist distributing National Front leaflets out of our street. Or my nan, a fearless dinner lady, sitting beside an Asian man on the bus who was being racially abused. I was taught that if you have a voice, you use it to help others.

I’m not so arrogant that I believe my personality alone will transform our fortunes. And I know that sometimes my passion gets the better of me. But who you are, where you come from and what you care about matters. Politics has shifted in a fundamental way. All over the world we see that it isn’t enough to offer big change, you also need a big personality.

I’m standing as leader because I believe I can combine the energy and activism of the past few years with an ability to speak in a language that shows our lost voters that we get it, that we care, that we are back as their party. That’s how we begin to give people hope again.