It’s only seven years ago, but 2015 feels a lifetime away given all that’s happened around the world since. At the tail end of that year, almost 200 countries adopted the Paris Agreement on climate change – a single agreement on cutting the greenhouse gas emissions that are causing global warming.
But 2016 saw the beginnings of upheaval with, first, the Brexit vote in the UK and then election of Donald Trump to the US presidency. One of Trump’s first acts on assuming office in 2017 was to announce that the US would withdraw from the Paris Agreement, something that...