In November 1940, Winston Churchill sent a telegram to Franklin Roosevelt expressing relief both at the US president’s re-election and the victory of his anti-appeasement policy. “Things are afoot which will be remembered as long as the English language is spoken in any quarter of the globe, and in expressing the comfort I feel that the people of the United States have once again cast these great burdens upon you, I must now avow my sure faith that the lights by which we steer will bring us safely to anchor,” he wrote. As Keir Starmer and Emmanuel Macron prepare to...