As Tony Blair’s era as prime minister draws to a close, it is timely to reflect on the successes and failures of a decade of Labour government. The early hours of May 2 1997 seems like another age – indeed it is a testament to our success that we are witnessing the longest continuous period of Labour government in our party’s 100-year history.

I joined the Labour party in 1982. I remember knocking on doors in the 1980s and 1990s when people simply did not trust us to manage the economy. However unfair it may have been, the Tories were able to remind people of the winter of discontent, and convince voters that the economy was safest with them. Under Gordon Brown’s stewardship, Labour has earned a reputation for economic competence. Social justice and economic efficiency can be combined successfully – the past 10 years shows how it can be done.

I think there are three big, connected achievements of the past decade: reconnecting Labour with the concerns of voters in the centre ground; shifting that centre ground to the left; and killing the myth that Labour cannot manage the economy.

We vacate the centre ground of politics at our peril. There is no clash between our progressive, left-of-centre values and the concerns of the majority of British people. Where we have been weak has been in not making explicit that our policies are rooted in a strong set of values. For example, in education we (correctly) highlight the economic benefits of investment in schools and colleges, but neglect to stress that the focus of that investment is on the poorest communities, and that education is a weapon in the war against injustice, prejudice and poverty.

We can be rightly proud of the social reforms of the past decade: tackling disability discrimination; the Stephen Lawrence enquiry; maternity and paternity rights; and civil partnerships. It has been a big leap towards a truly open, diverse society, and in stark contrast to the Thatcher/Major years perhaps best summed up by the notorious section 28. A Labour government has committed the UK to abolish child poverty and to finally reach the UN target on development aid to the poorest people in the world. Progress on poverty both here and abroad has been made, but we still have a mountain to climb both in regenerating deprived communities here and in fighting extreme poverty overseas.

It is a genuine achievement that on so many issues the Tories have had to accept Labour’s reforms, having opposed them when we introduced them – the minimum wage, increased development aid, lesbian and gay equality, investment in schools and hospitals, and Bank of England independence, to name but a few. Of course, the Tories can’t be trusted to stick with these commitments were they ever to return to power, but it is a tribute to our success that they can no longer credibly oppose us on large swathes of policy. The centre ground has been shifted to the left.

Despite all this, trust in politics and government is at an all-time low. Constitutional reform dominated the early years of Labour in government but the momentum for democratic change has been lost. After 18 years in opposition, Labour ministers understandably grabbed the levers of central power, but there is now an overdue consensus that local democracy should be revived. Robin Cook made some progress in seeking to modernise our parliament to reconnect with the people, but much more needs to be done. Being on the left means having faith in politics as an instrument of progress – that is why it is so important for Labour to stand for a politics that is clean, open and fair.

For many, Blair’s legacy will be summed up in one four-letter word: Iraq. His commitment to an active, interventionist foreign policy has been contentious, though most people backed him in Kosovo, Sierra Leone and Afghanistan, and many demand action now in Darfur. Nobody in 1997 would have predicted that foreign policy would so dominate Blair’s decade, but that was before 9/11. Clearly there are many, difficult lessons to be learnt from the Iraq experience, and it is important that progressives have this discussion in an open and constructive way.

There is a danger that we become gloomy about the political situation with the Tories ahead in the polls. Yet what is remarkable is that the terms of trade in politics have shifted towards us. Mistakes, of course, have been made and we must learn from them. The party leadership should not be afraid of open debate and discussion as we shape a programme for what we hope will be Labour’s second decade in power. Whatever short-term difficulties we face, we can draw strength from knowing that our Labour values have enduring relevance.

The moment I defeated Michael Portillo 10 years ago has become a symbol of the 1997 Labour victory – the third greatest television moment ever! Let us regain some of the hope and optimism we had then as we prepare for the challenges ahead.