From the article: A new Left has to be an ecological Left, or it won’t be left at all. Environmental change ‘changes everything’ for the Left too, Naomi Klein argued. Capitalism requires constant expansion, an expansion predicated on exploitation of humans and non-humans, that irreversibly damages the climate. A non-capitalist economy will have to sustain itself while contracting. But how can we redistribute or secure meaningful work without growth? There is not yet a concrete ‘economics of degrowth’. Lamentably, Keynesianism is the most powerful tool the Left, even the Marxist Left, has for dealing with issues of policy. But this is an economics of the 1930s when unlimited expansion was still possible and desirable.