Caroline Lucas is quite right to ask the green question in this election

The Labour Party has not stepped into the gap with a convincing green programme

Caroline Lucas has been on the streets of London promoting the importance of green issues, sadly all to sparse in the other parties’ manifestos (PA)

Caroline Lucas, the co-leader of the Green Party, was carrying a giant green question mark around London today to make the point that climate change has hardly featured in the election so far. She is absolutely right. The failure of the two main parties to talk about the environment has been one of many disappointing features of the campaign.

Ms Lucas makes the point that climate change is hardly mentioned in the other parties’ manifestos, and that the issue has not come up in any of the big TV set-piece events so far. The Conservative Party has retreated from David Cameron’s green respray, which was one of the more hopeful features of the 2010 election.

That retreat began during the Coalition years, despite the presence of the Liberal Democrats in government, but it turned into a rout under Theresa May. The new Prime Minister has junked a lot of her predecessor’s legacy, including the green rhetoric. It may not have gone very deep, but it was better that the Government was notionally committed to environmental sustainability than not.

Unfortunately, the Labour Party has not stepped into the gap with a convincing green programme of its own. Jeremy Corbyn’s politics also marks something of a break from that of his predecessor’s, and one of the changes is that he seems to be less interested in the politics of climate change.

Fortunately, some of the momentum inherited from the last Labour government and from the early years of the Coalition is still rolling through the British power generation system. In last week’s sunshine, the contribution of renewables exceeded 40 per cent of total electricity for the first time, with 24 per cent coming from solar power. This could have been the chance for visionary leadership to make the case for preparing the next push towards a low- or zero-carbon future. It is a shame that Ms Lucas’s party, which has such limited electoral prospects, should be the only one making this case with any conviction.

On the other hand, the most urgent question for those concerned with climate change is what is going to happen in the United States, rather than here. Donald Trump, having listened to world leaders on his first foreign trip last week, said that he will decide this week, now that he is back home, what he intends to do about the Paris climate change agreement.

So far, the global green movement has focused its energies on trying to keep the US in the Paris agreement. It was the breakthrough moment, in April last year, when both the US and China signed up to a global system for restraining the growth of greenhouse gas production. It seemed to offer the prospect, finally, of concerted world action on the problem.

Recently, however, it has been suggested that, if President Trump were to repudiate the agreement, that would be better than if the US were to stay signed up to it in bad faith. As The Independent reported last week, Luke Kemp of the Australian National University argues that if the US remained a signatory, but failed to live up to its commitments, this could give other countries, such as Saudi Arabia, cover for backsliding.

In the end, however, it must be better for the world’s second biggest greenhouse-gas emitter (China is the biggest) to be part of a global agreement. If the US pulls out, other countries might follow and the Paris agreement could start to unravel.

The big green question of this election, then, might be whether Theresa May has any influence on the President whom she rushed to see within days of his inauguration. Sadly, the realistic answer is probably no. Or, rather, that if she did have a small amount of leverage, she would be unlikely to use it on the question of climate change, for fear of aggravating an important trading partner that Britain will need more than ever after leaving the European Union.