“…To this end, we looked for (1) the major emitters of greenhouse gases, since the policies and implementation experiences of such countries are of global importance; and (2) countries which have shown markedly different responses to climate mitigation, compared to one another; or (3) countries which have experienced dramatic shifts in implementationeither rapidly moving from a position of opposition or ambivalence regarding RE to strongly promoting itor shifting in the other direction, suddenly opposing RE and backing fossil fuels instead. With these criteria, we chose the following cases: (1) The United States, the world's second biggest annual emitter, whose governments flipped from providing cautious support to clean energy policies (under Presidents George W. Bush and Barack Obama), to directly opposing them (under President Trump); and (2) China, the world's biggest annual emitter, which has shown strong and consistent support for cleaner energy, but whose projected expansion of coal power risks tipping the world beyond the Paris Agreement (Wang et al, 2020). 1 For Europe, which as a bloc is the world's third largest emitter, we selected two major economies which represent sharply opposing trajectories of European climate policy implementation: Spain, which moved from strongly supporting RE to strongly opposing it (Alonso et al, 2016), subsequently reinstating support following a change of government; and Germany, which moved from a low level of national support and strong dependence on fossil fuels to become Europe's most important advocate of the clean energy transition (Hake et al, 2015).…”