Geoffrey Lean: John McCain, father of right-on, green Republicanism

The American press may not have noticed, but the environment is the coming issue in the election

"Save the planet. Vote Republican!" Right now that may not seem the most credible of political slogans – up there, perhaps, with "You can trust Tony Blair" and "Gordon Brown cheers you up". But, after last week, it could soon be adorning bumper stickers throughout the United States.

For on Tuesday, Florida crucially threw its weight behind the American politician with the best record in taking action on global warming. Not Al Gore – who lost the presidency in the Sunshine State eight years ago, when the future of the climate appeared to hang on those fateful chads – but the now-leading candidate for the Republican nomination, John McCain.

Gore may have talked a lot about climate change both before and after his vice-presidential stint, but he did virtually nothing while in office: during the Clinton-Gore years US carbon dioxide emissions rose nearly 10 times as much as in George Bush's first term. Instead it is McCain who has been spearheading efforts to cut the pollution in Congress.

And while Gore gutlessly refused to campaign on the issue that he has long considered the most important of all – fearing it would cost him votes – McCain made it one of the defining features of his presidential bid, sticking with it even when his drive to the White House appeared to be stalling last year. So, as things stand, it is the leading Republican candidate who has the most longstanding green cred in the public mind.

Few would have forecast any such possibility when the Toxic Texan was dubiously elevated to the world's most powerful office at the turn of the millennium – the rapid emergence of global warming as a right-wing cause.

It began with the highly improbable Arnold Schwarzenegger, the Hummer-loving Terminator, who – on being elected governor of California – took up the issue more vigorously than any other political leader. And it crossed the Atlantic when David Cameron, who had shown no discernable previous interest in the subject, adopted it first to help win the Conservative leadership and then to detoxify his party.

Next up was Angela Merkel, elected at about the same time to the German chancellorship, who quickly made her government much more environmentally friendly, both at home and in interntional negotiations, than the red-green coalition that preceded it . And now – though so far little noticed in this country – France's President Nicolas Sarkozy is beginning to implement the world's most ambitious and thorough-going green policy revolution.

True, Mitt Romney – now far behind McCain, but the only other serious Republican contender – is attempting to buck the trend, asserting that his rival's policies would cost each American $1,000 and insisting that climate change is for the rest of the world to solve.

But if there were no hypocrisy in politics, there would be little or no difference between the two. For Romney has, in fact, been a pioneer of the new green conservatism. As governor of Massachusetts until last year, he was another of the first American politicians to espouse policies to reduce greenhouse gas emissions. He changed his stance as he began positioning himself for a run at the presidency. This helped to establish a reputation for opportunism that has gravely damaged his candidacy, but he believes it saved him when he won last month's primary in Michigan – home of the Detroit car industry.

But last week Romney ran out of road in Florida. More precisely, he ran into yet another new right-wing eco hero, the pivotal state's popular governor Charles Crist. Affectionately known as Chain Gang Charlie for his proposals for the treatment of state prisoners earlier in his career, he has made the once-liberal cause of climate change one of his signature issues – laying out a programme to slash the state's greenhouse gas emissions by a radical 80 per cent by 2050. He endorsed McCain, sealing his victory and putting him far ahead.

The front-runner's greenery may also help him on Super Tuesday this week. Nine of the 20-odd states that hold primaries the day after tomorrow are already on their way to making emission reductions of their own, and opinion polls are running strongly in favour of action. Even in conservative South Carolina, six times as many Republicans support measures to cut carbon dioxide as oppose them. Yet more surprisingly, even 80 per cent of Detroit car workers back proposals to decrease exhaust emissions, despite Romney's success with the dissenting party faithful.

And Ken Mehlman, manager of George Bush's 2004 campaign, says the Republicans cannot hope to attract independents in the presidential election unless they propose "specific solutions" to climate change.

McCain is no natural greenie; in his campaign against Bush eight years ago he was dogged by a heckler dressed as a penguin, protesting at his lack of concern over global warming. But he quickly became convinced by the climate change science, called the President's position "disgraceful" and, since 2003, has successively introduced three bills to enforce action across the country.

In truth, his proposals now look mild besides those being put forward by the two remaining Democrats. Both Clinton and Obama may have been comparatively late in coming to the issue, laying out their plans in the autumn, but they have been vigorous in making up for lost time. Both support the same 80 per cent reductions as Governor Crist. By comparison, McCain's current bill would curb emissions only by 30 per cent. Both Democrats have adopted ambitious increasing renewable energy targets, while McCain has not.

But this is all to the good, because it means a bidding war, all but unnoticed, incidentally, by the American press, on global warming has begun. All three leading presidential candidates in the race propose dramatic action, so that prospects for international action will be very different once George Bush departs. As Phil Clapp, deputy managing director of the Pew Environment Group and perhaps the shrewdest observer of US environment politics, says: "It is now clear that the climate will be a top priority for the incoming president." It's enough to make you want to buy a bumper sticker.

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