The climate change debate continues to rage. Though the science remains “unsettled,” what does seem settled is that President Trump will withdraw, again, from the now infamous Paris Climate Accords. Importantly, those accords are centered on pledges made to modify national energy policies.

A decision to exit the Paris Accords is no mere gesture. The central fact for citizens everywhere is that putative “climate solutions” would deploy trillions of dollars and implement mandates and diktats for the supply and use of energy in every aspect of society.

The stated rationale for proposals to alter completely how civilization is fueled is the need for an “insurance policy” against future climate catastrophes. In that framing, the climate-fearful argue that some possibility of consequential future harms warrants the “responsible” decision to “buy” insurance now. But this often-argued “insurance” construct assumes that we know enough to say that the consequences of future climate change justify paying for the insurance—and collaterally, that we know the “insurance” itself will be affordable.

It turns out that we do know quite a bit about both those domains. As we outline below, reality tells us that the climate-change consequences that we’re trying to avoid will be modest—and that the costs of the “insurance” are staggering.