A White House 'sceptic': Would it matter?
Leo Hickman, among other talents a realistic candidate for the title of "world's most prolific enviro-tweeter", posts an analysis of the US political scene in The Guardian this week.
His conclusion: "The world needs to prepare for a climate sceptic defeating Obama".
The analysis rests on the quantifiable. In the first place, virtually all declared Republican presidential candidates have man-made climate change down as a hoax, or at least as something where the jury is out.
In the second place, President Obama's approval numbers are the worst they've been since he took office - 43%, as opposed to 53% who disapprove.
To be sure, climate change isn't the issue that's put him there - it's the economy, stupid.
But that doesn't alter the conclusion that he is potentially beatable.
There are of course many months to run in this campaign, and the shape and persuasion of the eventual Republican candidate is far from certain.
It's also possible that the Republicans will end up in the situation that befell the UK Conservative Party just a few years ago, wherein hard-core party members chose leaders on the basis of ideological purity, and in doing so ended up with prime ministerial candidates who were so unpalatable to the wider and more moderate electorate as to be virtually unelectable.
In particular, the question arises of whether the public approves or disapproves of the shenanigans in Congress over the recent budget.
An analysis by retired Republican staffer Mike Lofgren raises the really profound question of whether the current crop of congressmen actually want to make the government work, or whether their anti-big-government credo now permeates their thinking and tactics to the extent that they actually work towards gridlock, stalemate, and general public dissatisfaction with the political process.
"Everyone knows that in a hostage situation, the reckless and amoral actor has the negotiating upper hand over the cautious and responsible actor because the latter is actually concerned about the life of the hostage, while the former does not care," he writes of the budget negotiations that threatened to put the US in default, and that did lead to a downgrading of the nation's credit rating.
"The attitude of many freshman Republicans to national default was 'bring it on!'"
If this brand of what my colleague Jonny Dymond referred to as "red-meat Republican politics" does appeal, then presumably one of the rawest of the candidates will win the race, and a climate sceptic (or denier, as you prefer) will indeed line up opposite Mr Obama.
If not, Jon Huntsman or Mitt Romney - according to a New York Times analysis, the one-and-a-half candidates who don't plug the hoax line and who are more moderate on most other issues too - may yet win the nomination.
Suppose one of the "red-meat" candidates does come out on top, and does defeat Mr Obama - how does that change the outlook for US climate and energy policies, and for international discussions such as those within the US system on climate change, or within the G20 on clean energy?
In one sense, it'll change little. The balance of power in Congress, even in the Democrat-controlled Senate, means that comprehensive legislation to restrict carbon emissions is already further away than it has been at any point since George W Bush handed over the keys to the Oval Office.
Legislation is definitely not going to happen if a climate sceptic takes over - but it isn't going to happen if Mr Obama wins either. Ditto a strong US commitment in international climate change talks.
On the energy front, the G20 and Asia-Pacific Economic Co-operation (Apec) forum pledged to phase out fossil fuel subsidies back in 2009.
One suspects a red-meat Republican would cast such a pledge from his or her plate. But whether it makes any practical difference is another matter, given that the pledge had no timescale, no financial levers and no legal form.
Domestically, it's tempting to ask how the Environmental Protection Agency (EPA) would fare if the stabbings it's currently receiving from the forks of right-wing Congressmen are complemented by slicings from the knife of a right-wing Republican president.
As former Friends of the Earth chief Tom Burke wrote in the ENDS report in July (paywalled, unfortunately), the vitriol levelled at the agency is particularly ironic given that it and the swathe of legislation it administers were largely created by a very Republican president, Richard Nixon.
But the impacts of an EPA neutering would be largely confined within US borders, and reversed relatively easily if voters came to mourn its absence.
Decisions will have to be taken fairly soon on oil drilling around US coasts, especially in the Arctic, and whether to pursue more exotic fossil fuels such as methane hydrates.
But these decisions are not for the federal government alone. States will have their say; and in the north, native American peoples and their concerns will also be factors.
Already, the green fervour engendered by Mr Obama's election has subsided to such an extent that the most dramatic programmes on topics such as renewable energy, carbon taxation and automobile fuel standards are coming from states, not Capitol Hill; and a national election won't necessarily negate those programmes.
Given the politics yet to unfold, it may be a bit premature to assume that a climate change sceptic or denier will be running the White House when the dust settles.
But the rest of the world has to recognise that whatever transpires, the US is unlikely to be pushing a radical green line any time soon.
Then again, it has been this way since the hanging chads of Florida carried Mr Bush to the White House in 2001.
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