What world is Brexit being launched into?

Simon Kuper reflects on the key political factors that will be present during Britain’s exit from the EU. Four and a half years after the United Kingdom went to the polls and decided to part ways with Europe, Brexit will finally become an absolute reality on the 1st of January 2021, when the transition period bounding the country to EU rules will end. Where do all the parties involved stand now? The Financial Times' columnist analyses.