At the Oxford Literary Festival on Sunday I went to a session called 'What's the big Conservative Idea?' with Ed Vaizey, Peter Hitchens and Iain Dale as the panellists.

I expected to come away depressed about the energy, enthusiasm and sense of purpose that the Tories were displaying ahead of what they expect will be a return to office in a little more than a year's time. I thought about what a similar discussion back in 1996 on Labour's Big Idea might have looked like – a vision for a fairer Britain – with the New Deal, minimum wage, waiting lists down and new rights for workers. But, instead of coming away depressed I left with a renewed sense of optimism that we have everything to play for at the next election.

The session started with Vaizey voicing his scepticism about big ideas. After trotting out some general uninspiring platitudes – he believes in community, individuals and not in over-bearing government, the debate rapidly degenerated in to an argument about Europe – to pull out or not, re-negotiating the treaty of Rome etc. Clearly Hitchens was the main anti-European protagonist, but Dale pointedly noted that the party had discouraged members from discussing Europe because it is still so divisive in the party.

There is an opportunity here to exploit these divisions more. Voters like nothing less than a disunited party unready to govern. The issue also demonstrates that the Tories want to back away from international engagement exactly when the challenges we face are so global in their nature.

The final statement asked by a member of the audience summed up the feeling in the room – "I feel quite uninspired, there is nothing positive for why I should vote Conservative and you are just relying on the unpopularity of the government". There is no sense of optimism and excitement about having a Cameron led Conservative government – not like in 1997 where disillusion with Thatcher and Major's eighteen years in office was coupled with high expectations and a sense of optimism about what Blair's Britain could achieve.

I am sorry I can't tell you answer to the event's title – because there is no answer, there is no big Conservative idea.

And because there is no big idea about what to do with power there is no rallying call, and no enthusiasm for a Cameron government. This presents Labour with opportunities and gave me a new sense of optimism about our chances in 2010. We need to renew our own vision, not a re-hashed 1997 Pledge Card, but a clear set of value-based policies of what Labour would do with a fourth term.

If we can offer voters hope and vision, we can win again.