Image copyright Getty Images Since the US election result, there has been consternation among climate campaigners and many environment ministers, especially those attending the annual Conference of the Parties (COP) in Marrakech.
The fear, and fury of the green response to Donald Trump is understandable.
Here's a man who has promised to "cancel" the Paris Climate Agreement, and who tweeted __that climate change was a hoax invented by the Chinese - though he did seem to dispute this accusation during a presidential debate.
However his admiration for the coal industry and his determination to revive it are not in doubt. None of __that sits well with those who believe that climate change is the greatest threat facing the planet.
But there is another school of thought that says that a Trump presidency could actually aid the fight against climate change.
'Overblown as his haircut'
The Paris agreement became part of international law in super-quick time, mainly because countries were aware of Mr Trump's threats to wreck the deal.
"His negative impact is as overblown as his haircut," said Joe Ware from Christian Aid.
"He's already generated the fastest coming into force of any treaty with the ratification of the Paris treaty in record time."
If Mr Trump decides to withdraw the US from the Paris Climate Agreement it would be a blow to the deal - but not the terminal one that many fear.
China, India and all the major emitters have reiterated their belief at this conference that the deal is irreversible and they will honour their commitments. Mr Trump appears to have forged a spirit of unity among all parties at the conference, even the World Coal Association (WCA).
"What we are focussed on is how do we implement the Paris agreement and how do we support countries to implement their nationally determined contributions," said Benjamin Sporton from the WCA.
"That's what Marrakech has been about, and from our perspective that needs to include the focus on low emissions coal technology."
The spirit of unity is also likely to be felt in the US if the new president makes good on his promises to boost coal exports and allow the extraction of oil and gas on Federal lands.
Environmental movements are already reporting an increase in membership enquiries.
If President Trump revives the Keystone pipeline, he could galvanise a new generation of climate activists.
"Young people in the US know well that it is ridiculous to be denying climate," said former Irish president and UN climate envoy Mary Robinson.
"In so far as it is, it seems to me to be an issue that some lobbyists want fossil fuel to continue, that is a last gasp, like the tobacco industry and it's not going to succeed."
Money for green measures
One of Mr Trump's most prominent campaign promises has been on revitalising America's infrastructure.
This is an issue on which he might garner much political support.
City mayors and other authorities are likely to want to see some of that cash spent on green measures like energy efficiency in offices, homes and buildings.
It saves energy, which saves money - and reduces emissions significantly.
So will insulation make America great again?
"Energy efficiency is the silver bullet for a lot of our problems with climate change and energy poverty," said Joe Ware.
"That has got an appeal to conservatives and liberals and that could really be something that becomes a Donald Trump cross-party success story."
If Trump spends heavily on infrastructure and pursues the use of gas for generating electricity and also spends money on developing cleaner coal, it could turn out that his impact on US emissions will be more positive than most people believe.
And even if he isn't a climate angel, there are other factors that would limit the damage he could do to the progress the US has already made. US Cities and states have already taken significant action. They won't be turning back.
"We survived eight years of George Bush and we were in a much more fragile system then," said Joe Ware.
"We didn't have Paris, we didn't have China leading the way, we didn't have the technology transition we are in at the moment.
"I think he'll be more limited than a lot of people are getting worried about now."
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