From what I understand, French is and has been for a long time the international language of diplomacy. This is very hard for me to understand, because every time anyone tries to speak French around a French person, they always make rude faces and sneer and complain about the speaker’s pronunciation and grammar and such. That couldn’t possibly make it easy to avoid war, I shouldn’t think! (For this reason, I wonder if it’s secretly responsible for every war since it was adopted as the language of diplomacy?)
But I believe I have this figured out now why French is still the international language of diplomacy: When two opposing sides who are at war begin speaking French in diplomatic talks, the French people all hold their noses contemptuously, roll their eyes mockingly, and insult everyone’s pronunciation and grammar, and then both sides find that they have common ground after all, in hating the French who snob them off for their efforts to speak the French language. And so, finally finding common ground, they make friends and end the war. (Could this be it? It’s all I can think of for why French is still used for diplomacy.)
(Just kidding! I love the French and the French language. But the French are extremely hard on French speakers for whom French is not their mother tongue. That part is absolutely true. And that’s why I think it might make more sense to switch to using another language for diplomacy: one where native speakers are generally delighted to hear others attempt to speak their language despite perhaps mangling it. And I think that language is Spanish.)