It will be easy for Liberal Democrats, absolved by the voters from the responsibilities of office, to shelter in our comfort zone. But it would also be very, very wrong. My leadership campaign is founded on the opposite argument. We must first learn the lessons of our time in government. Having told the electorate in 2010 that we would be different from the others, we were nowhere near different enough.
But it is the future of the Liberal Democrats that occupies me most - along with those many thousands who have chosen to join us since the terrible defeat of 7 May. We must urgently create the new bonds of trust and hope that will be needed if we are to play our full role in securing a better future for Britain. The next few years can't just be about making ourselves feel better; we must be far more ambitious than that.
That means broadening our policy and political thinking, daring - once again - to be radical and challenging. It is why I am proposing a renaissance in our approach to political action and debate, reaching out to include the many - particularly young people - who share our values and instincts but are put off by closed party structures and, even worse, by tribalistic political thinking.
Our task now is not just to devise short-term tactics or louder opposition. We will succeed when we have a long-term, coherent and persuasive set of strategic ideas for Britain.
The good news is that Liberalism fits our age. Britain has become less collective, citizens and consumers feel more empowered and many individual rights - through equal marriage for instance - are better recognised.
But - and this is the bad news - much of our economy, society and politics remains thoroughly illiberal and conservative.
For instance, our economic performance is stunted by entrenched privilege at the top, and cycles of deprivation at the bottom.
Our economy will only do better - over the long-term - if everyone sees the benefits of growth. And if we take advantage of all the talent that is available to us.
But that doesn't mean just old-fashioned re-distribution. We need new ideas for this new age.
Liberals have always been supporters of enterprise and innovation, and we are instinctively at home with mutuals and social enterprise. We should be natural adopters of the networked, digital, go-ahead businesses of the future. We should be planning and spending now for improvements in our infrastructure that will provide a return on that investment for decades to come. A successful economy is an essential part of an outward-looking, open-minded society that cherishes skills, education and social justice.
A Britain where everyone can thrive according to their abilities must be the goal of every liberal.
Prosperity must be sustainable, too. We must be much bolder in our commitments to the environment, building on the record of Ed Davey and Vince Cable in government. Britain is still missing business opportunities that will both improve efficiency and reduce carbon consumption.
Our liberalism also demands that we create public services that put the citizen first. They should be responsive, flexible and adapted - sometimes radically - for the very different lives that people lead today. I want a public sector that is more self-confident and innovative, but ruthlessly focussed on delivering the big-ticket outcomes of improved educational achievement, better health for all, falling crime and welfare support for those who need it most.
And, on behalf of taxpayers, we should continue to press with determination for greater value for money. Digitisation will play a massive role, here. This is the best way to reduce the deficit and put the public finances on a sustainable footing.
George Osborne's new approach - which seems based on a lack of trust in his own competence - will not help us get to the right place. Britain needs a pragmatic and responsive approach to reducing the deficit. We must not do so in a way that impoverishes the nation or undermines key public provision.
And - where it is right to do so - we should be prepared to use the power of the state to overcome market failures. Housing is a good example. Why not enable government to provide new housing on public land at market rents, while using the returns to invest in more affordable housing? Since we know that inequalities of opportunity impact very early in every child's life, let's make nursery education the top priority that it needs to be.
There are many other issues that we will need to champion. For instance, we will not just play our part in securing Britain's future in the EU. Liberal Democrats must, once again, lead the movement for a more engaged Britain that plays its full role in the world. The case for political reform is as strong as ever.
But a modern liberal party must also show how to deliver both prosperity and social justice. The fightback begins here.
Norman Lamb is the Lib Dem MP for North Norfolk, and is standing to be the next Lib Dem leader - for more information, visit his campaign site here: backnorman.co.uk