Climate hawks are familiar with the framing of climate policy credited to White House science advisor John Holdren, to wit: We will respond to climate change with some mix of mitigation, adaptation, and suffering; all that remains to be determined is the mix.

It’s a powerful bit of language. It makes clear that not acting is itself a choice — a choice in favor of suffering.

But in another way, Holdren’s formulation obscures an important difference between mitigation (reducing greenhouse gas emissions to prevent climate effects) and adaptation (changing infrastructure and institutions to cope with climate effects). It makes them sound fungible, as though a unit of either can be traded in for an equivalent unit of suffering. That’s misleading. They are very different, not only on a practical level but morally.