In 2016, parallels were drawn between the election of Donald Trump as U.S. president and Britain’s vote to leave the European Union – as a victory for populist politics. Four years on, Trump is up for re-election against his Democrat rival Joe Biden, while Britain will leave the Brexit transition period at the end of the year. As Henry Ridgwell reports, many observers say Britain’s post-Brexit future could be closely tied with the outcome of the November 3 U.S. presidential election.