Explanation: France and the UK began WW2 fighting as allies against the unprovoked aggression of Nazi Germany. However, a lightning campaign fueled by a dictator’s madness and meth - literally on both counts - Hitler insisted on a maneuver his generals (and French generals) considered impossibly risky, and methamphetamines were widely distributed to Nazi troops, especially tankers, in 1940 - knocked France out of the war.

Under Field Marshal Petain, who was appointed the head of the French government on the basis of his national popularity and WW1 service, the French Third Republic surrendered to Nazi Germany. While France was in a poor position, it was nowhere near destruction - Petain surrendered because he was a fascist sympathizer, and an opponent of the ‘liberalism’ of the Third Republic. Those who sided with Petain became known as “Vichy France”, while those who fled France to continue the fight and refused to recognize the surrender became known as “Free France” (by the Allies, obviously; both claimed to be the legitimate government of France).

After France’s surrender, a humiliating peace treaty was imposed on Vichy France, and Vichy France changed to ‘neutrality’ in WW2. Winston Churchill, prime minister of the UK, made a demand of the Vichy French government - to take their fleet out of the reach of the Nazi regime. They refused, considering it a matter of pride that they could defend their own fleet from seizure.

Churchill did not think pride a sufficient guarantor, and ordered an attack which crippled the French fleet. This has been a sore point ever since, with defenders and detractors of the course of action.