Following embarrassing reversals on the Mexican wall, the Muslim immigration ban
and other signature policies, he sees rejecting accepted orthodoxy on climate change as an easy deliverable to please his populist base.
Too bad it fries the planet. He was elected on this pledge, and he plans to deliver.
Canceling the Paris deal is a classic post-truth policy. Based on the outright denial of overwhelming scientific reality -- and telegraphed in suspense-building gameshow style this week via Twitter and conflicting media teasers -- it is Trump at his most callous, ignorant and attention-seeking.
As a former reality TV star, Trump cares about how things look, not how they really are. Torpedoing climate efforts is the ultimate "up yours" to liberals -- after all, that's the point. The aim is symbolic, but faced with higher carbon emissions and consequent disastrous global warming, our children may not see it that way.
My guess is that far from undermining the determination of other world leaders to cut carbon emissions, Trump's action will have a galvanizing effect on the Paris accords. It will prompt other countries to redouble their efforts, precisely in order not to let Trump be seen to win this vital battle over the future of the planet.
The European Union in particular, led by Germany's Angela Merkel, has no intention of letting Trump get away with this kind of global vandalism. On climate, the EU is united far more than on any other issue. Brexit will make no difference -- all mainstream political parties in the UK back Paris. The move will lead to the isolation of the Trump administration and further corrode international goodwill towards America.
It will also mean the US ceding climate leadership to China, a mantle Beijing is only too eager to assume. The Chinese want both to solve their crippling smog problem and look like a responsible global superpower. Their considered and long-term approach is cast in direct opposition to the self-centered showman now inhabiting the White House.
And the Chinese approach is not merely altruistic. China's leaders have long recognized the economic opportunities in moving aggressively into clean energy technologies. Solar is now cheaper -- as well as cleaner -- than coal in many developing countries.
Trump, who likes to pose as a successful businessman, seems not to understand the value of innovation. Instead he seeks to turn the clock back to an imagined golden age of fossil fuels. If America falls behind in the clean energy revolution, it is not Trump who will pay the price.
For the environmental community, this looks like a rerun of George W. Bush's withdrawal from the earlier Kyoto treaty in 2001. That political gambit lost the world a decade. Trump's may lose far more -- if we let it.
I now expect to see the full fury of the environmental movement -- including just about everyone except for the Breitbart right -- to be turned on the US coal industry, the only powerful economic player to oppose climate action. (Even Big Oil now backs Paris, along with most of the rest of corporate America.)
Expect determined efforts to defund coal mining, huge divestment campaigns against coal company stocks and rallies to close down coal-fired power plants all across America.
The coal industry has now put itself squarely in the cross-hairs of an intense global reaction. Hitting coal is a way to hit back at Trump -- where it hurts.
Trump will thus have achieved precisely the opposite of his intended effect.
Instead of shoring up coal jobs, he will have made a full-scale "war on coal" -- and US coal in particular -- the pre-eminent moral cause of our time, just as the struggle against apartheid was for an earlier generation.
And -- ironically for such a divisive person -- he will have helped bring about an unprecedented degree of global unity, albeit against his own administration. For that, we can perhaps be grateful.