Profit = Revenue - Costs.

Developing nations are up and coming polluters that will go through a particularly polluting industrialization period (like the US and the UK did between 1870-1930).

We could help them skip that phase, if we are careful about it and have some measure of control over incentivizing green-energy expenditure.

But instead we will have no say in those proceedings now that we are exiting the Accords over the next 4 years.

The amount we would have given is less than 1% of what we give to Israel every year. It's even less than 0.1% of what we are providing to the UN already, every year.

We could have established our own business interests in those very same countries too, with the burgeoning green-energy market. Which is something even a "businessman" like Trump should have understood. Now we will miss out on countless international business opportunities.

Maybe it won't hurt the US much, but it's not helping either. We are choosing be to stagnant. Which doesn't sound very "high energy" to me.