Second, it’s clear that what the United States does matters, but it matters most in the context of what other countries do — and that in judging U.S. action, we have to look at that action across the entire century. This is, again, why Trump alone can’t doom the climate, unless he starts some kind of grand wave of climate isolationism or long-term inaction.

Therefore, based on this analysis — and Climate Interactive aren’t the only number crunchers out there — here is what we can say about a Trump presidency and the planet. It’s basically all about legacy and influence. Knocking the United States off of the Obama administration’s trajectory of lowering emissions, and doing so for only four years, is not that big of a deal if the rest of the world races ahead anyway, and if the United States rejoins the action in four or even eight years, muddling along without much emissions growth, or even emissions declines, in the meantime.

But if there is a longer-term reversal of progress, and if it poisons the international mood that currently favors action, that’s where you start to worry.

Oh, and one more thing: Let’s remember most of all that staying below 2 degrees is extraordinarily difficult even without Trump. That’s why middling pathways like the one above representing some U.S. and global action, but not enough, sound pretty realistic right now. In these possible worlds, the planet may not totally cook, but its change would still be sweeping.

The gist is that keeping climate warming under control was exceedingly hard before the 2016 U.S. election and will probably be still harder after it — but we still need to focus on the long term, and consider the entire the globe.