[On coronavirus's effects on international cooperation] What's happening is that all countries have turned inward. The political support in most countries for extensive international engagement has been fraying. That's been going on for a long time, because of the nature of international cooperation and the fact that it's not delivered benefits back to populations widely.
It’s not surprising that the most ardent nationalist populists—in Brazil, the US, EU skeptics in Britain—are also the most skeptical of Paris. But that whole agenda is deeply problematic for climate because ultimately what you need is a set of institutions and some measure of cooperation that helps diffuse good ideas and products around the global economy.
[On the Trump administration's rollback of vehicle efficiency standards] One thing we’ve learned from the Trump administration is be careful what you ask for. The auto industry wanted a smoother glide path to a more efficient future. Instead what they got was the populist politics of the far right, which is blowing up in their faces.
[On the future prospects for electric planes for short-distance flights] There is no question that this will be unbelievably complex and costly. The only reason to do it is if we think that opening niches in the U.S. (and in other countries) will be the starting point to a broader application — eventually to medium-haul flights and beyond. One does this only if we need to make deep cuts in emissions. If we do shallow decarbonization there are other options that are cheaper — more natural gas, more renewables. But shallow decarbonization doesn’t fix the climate. Only deep decarbonization fixes the climate.
The world’s diplomats have spent 30 years talking about the climate problem. That hasn’t achieved much. Global emissions of warming gases keep rising. Electric planes could be part of the solution. It’s possible that we’ll see people using them to take flights between cities like San Diego and San Francisco.