The Brexit vote and the election of Donald Trump will forever be linked in history. The two events took place within a few months of each other. Both were populist revolts that appealed to similar constituencies.

After Mr Trump’s election, Theresa May, Britain’s prime minister, was the first foreign leader to visit the new US president. A photograph of the two leaders walking hand in hand quickly became a symbol of the closeness of Trump’s America and Brexit Britain. For mainstream politicians in Europe, “Trump and Brexit” became shorthand for the forces that they were trying to combat.

But, as the months have passed, it has become clear that Trump and Brexit are not, in fact, identical twins. They are more like distant relations who are growing further apart with the passage of time.