The perfect is the enemy of the good.

The required reduction is 99.9% of greenhouse emissions for the next millennium. No institution has ever had that power, few have lasted that long, and even those few which have lasted that long underwent significant policy changes in that time. If we can’t make saving the planet cheap enough that even the greedy and selfish prefer to do that, then we can’t win at all.

But half-arsing it now gives us more tomorrows in which to create the better solution.