There seems to be an awful lot of pessimism around at the moment about our chances of dealing properly with climate change, especially after the failure of the Copenhagen conference last December, yet at the launch of the Government's post-Copenhagen strategy the other day, you mentioned your optimism more than once. Why is that? Is it because politicians need to show an optimistic face? Or are you an optimistic type of person? Or are you genuinely optimistic about our chances of keeping global warming in check, when a lot of good judges are not?
There is no doubt that Copenhagen had its disappointments, though I think its obituary has been overwritten. Indeed, since Copenhagen, we have seen more than 100 nations associate with the Accord and the targets in it now cover 80 per cent of global emissions, including the USA, China and India. That is a more comprehensive agreement than ever before, even though it's not yet legally binding.
Of course, there are major obstacles to making further progress. I'm sure we could both list a dozen. But every other great movement in history has also faced obstacles that seemed insurmountable. Those obstacles were defeated thanks to the power that campaigners have when they are determined to make a difference and have right on their side.
That is the spirit that led to the successes of the Labour movement on workers' rights, on the foundation of the NHS and in the major shift we have seen in social attitudes in Britain, as well as causes like anti-apartheid. I think we need to look at the cause of climate change in the same light.
Of course spirit alone is not enough, but pessimism isn't the way forward either.
It's partly a question of outlook: pessimism has never won a single progressive advance. And it's also an issue of conviction: the challenge of climate change is so profound and will affect all countries, so I am convinced we can build the wider will to tackle it comprehensively.
There is an old political saying, "don't mourn, organise". And that is what the wider climate change movement needs to do. Government needs to do it domestically and in Europe in driving forward ambitious plans for the future and we need to do it internationally as well.
Many thanks for that, which is fascinating in terms of principles and where you're coming from. But I wondered if I could ask you about practicalities, and in particular about China, which – as you are only too well aware – deliberately prevented the world community at Copenhagen from setting agreed international targets to reduce CO2 emissions. Many people concerned with climate change think to have a chance of halting rising temperatures, we have to cut global emissions by (at the very least) 50 per cent on their 1990 levels by 2050. In 1990, global emissions were about 22 billion tonnes, and if you cut back to 50 per cent of that, you're left with 11 billion tonnes of emittable carbon dioxide, for the whole world. Yet the Chinese are already emitting more than seven billion tonnes annually, and they intend to emit much more over the coming years (although they may slow the rate of growth). By 2050 they may be emitting all the CO2 that the world is allowed.
My view is that the Chinese will simply never agree to the 50 per cent global cut by 2050, as it cramps their economic growth impossibly, and that growth is what is holding their society together. It seems to me this is a structural problem in the shape of the world, which no amount of campaigning spirit will ever be able to get round. Or is that mere pessimism?
It is worth saying at the outset that it is significantly to its credit that China has put targets into the Copenhagen Accord and has made important commitments on renewables, afforestation and carbon intensity as part of that.
I agree on the benchmark of a 50 per cent cut in global emissions by 2050. But we are clear that developed countries will have to do more than developing countries in terms of reductions because emissions per person are currently significantly higher than in developing countries.
You're right, of course, that over the coming decades, developing countries like China will need to cut their emissions too. However, I think there are a number of forces in play that make it more likely that China will act than you think.
There is no doubt that the Chinese government understands the threat of climate change to their country and society. Greater drought and flooding as a result of climate change could be disastrous for China and it is very much in their national interest to stop that happening.
Secondly, cutting carbon isn't just good for a country's climate security, it is also good for energy security. Take the issue of oil. There are different estimates about the size of oil reserves and how easy they will be to extract, but any way you cut it, it is clear that economic development around the world is going to raise the price of this finite resource in the long term. In that context, technologies like electric cars and biofuels can become attractive on energy security as well as low-carbon grounds.
The third force is economics. It's not just that the economics of low carbon are changing as technology develops, making it cheaper for China to cut their carbon emissions. It is also that the economy of China will change. Over the period you are talking about, China is likely to shift towards a more-diversified economy, with less reliance on low-cost manufacturing. Again, that makes it easier to cut carbon.
It is for these reasons that we see China driving forward with their low carbon transition: investing in the green technologies of the future. We are determined to work with China and others to get the comprehensive legal treaty we need as well as the reductions in emissions.
Well, China may not be the only problem – we may have trouble closer to home. It became clear this year that a significant part of the British population was beginning to have doubts about the reality of climate change, and whether or not it was caused by human society. Why has this happened, and do you think it is likely to lessen the emphasis that politicians give to tackling global warming?
I write this on a train from Crewe having been in the Red Lion in Nantwich last night discussing precisely this with a first-time voter. He was sceptical about the reality of climate change.
There is no question we have a job to do to convince people. Why? Because climate change is an unusual threat: it's not an army massing on the border, it's distant from people's lives because the full consequences of today's actions will only be apparent in a few decades and it can fall prey to the natural (and healthy) scepticism that characterises our society today.
The problems of the last few months around UEA and IPCC obviously haven't helped. The people who believe the climate change threat is real should be the most assiduous about openness and transparency in my view.
That said, when I talked to the chap in the Red Lion about what the scientists had been telling me, the consequences for his world when our generations have passed on, he was less sceptical.
That is why all politicians have a massive responsibility to stand up and be counted on this issue. One of the disturbing things about the Tory party is that it has lots of sceptics in it and I see no sign that the leadership is willing to confront them.
We also need to do something else: inspire people with a positive vision of jobs, energy security and fairness. A Labour party member reminded me that Martin Luther King didn't say "I have a nightmare" but "I have a dream". The climate change movement needs to bear that in mind and talk as much about the dream of a better world, of which protecting our environment is a part, as it does about the nightmare.
But don't you think that, quite apart from climate scepticism, the massive economic problems the rich world now faces after the recession, and the enormous priority that will be given to shrinking deficits, will mean that climate change as a policy issue will simply take a back seat with most governments?
Not with us. Part of what I have tried to do over the last 18 months is to make climate change more than an environmental policy. It is about the future of our economy.
GE, Siemens, Clipper, Mitsubishi have all said they will locate offshore wind production here. Nissan have said they will make electric cars in Sunderland.
These things didn't happen by accident, but because we are creating the domestic market – we are the world leader in offshore wind generation – we are ensuring we have the skilled workforce and we are providing the incentives for companies to invest. So, we have provided an offshore testing facility in the North East, something the market on its own wouldn't provide.
Peter Mandelson has led the way on this since he became Business Secretary, kickstarting the green industrial revolution in Britain. That is a big contrast with the Tories. Kenneth Clarke says talk of an industrial strategy sends "shudders down his spine". In fact, what should send shivers down our spine is that he is someone who wants to be Business Secretary, and should be persuading investors to come to Britain, who says we shouldn't have any more onshore wind turbines, as he has.
For us, green is the future of our economy, about the quality of life for people and our energy security. We have shown a willingness to prioritise these investments with decisions on high-speed rail and a new Green Investment Bank. The next few years will mean much tougher times on public spending. But I think we can come through them greener, fairer, more secure.
On a final point, I wonder if could ask you – as a socialist, or at least, a believer in social justice, you obviously have a pretty well-defined political creed. Has being in charge of climate change policy for the last 18 months modified your outlook at all, or at least your sense of priorities?
It has changed my sense of priorities. I knew climate change was central before; now I have more of a sense of the scale of the threat, the promise if we do the right things, and the degree of difficulty as well.
Also I am more conscious that Labour politics needs the environment and also that the environment needs Labour politics. The former because the environment must be integral to our vision of the future; the latter because unless we instil values of fairness into the environmental debate, there is a real danger that we will fail at home and abroad.
At home, we need fairness because we can't have the poor ending up shouldering the burden of the low carbon transition – for example they need protection from higher energy bills. Abroad, unless we can have a politics of fairness, we just won't succeed in getting developing countries to be part of the solution, and we won't succeed in tackling the massive challenges the world faces.
There's something else as well. The discourse of modern politics is understandably about the politics of now: what can you do for me in the next five years? That is a very important question. But part of the challenge that the climate change cause faces is that the action we take now to counter the threat will have most effect in 50 years time. We really are fighting for future generations.
Are we therefore swimming against the tide of modern politics by even talking about this? My conclusion is no, but it does require the positive vision for now around jobs, quality of life and so on that I talked about in the first email and it also needs us to reach out and mobilise the younger generation who are more likely to face the consequences of today's decisions.
Indeed, to end where we began, my reasons for optimism lie most of all with young people. No offence to my generation or yours which has many people in it who get the issues, but I find that it is those younger than us who get it the most.
I had a fantastic presentation recently from students at Outwood Academy Adwick in my constituency about what they were doing in their school, and their thoughts on the international issues. The same is true of Upton High School in Chester where I was yesterday.
Political change can happen because politicians lead it, and it also happens because of millions of other influences for progress. Martin Luther King used to quote an old saying: "The arc of the moral universe is long but it bends towards justice." I believe that, not in some deterministic way, but because people make it happen. Fundamentally, that's why I am an optimist and why I'm in politics.
I've really enjoyed our exchange. Let's keep talking.
All best wishes