The Genius Trick That Won a War: Game Theory in the Musical Operation Mincemeat

Will the Allies invade mainland Europe through Sicily or Sardinia?

In World War II, Germany was dominating early and held mainland Europe. The Allies were looking to invade but also wanted to have as few Germans set up defending their specific landing spot as possible. How did they do this? That’s the subject of the musical Operation Mincemeat (based on the book with the same name and there was also a movie with the the same name).

(Note - some modest spoilers of the musical below. But not too many.)

In the video below (and at this link) we have excerpts from two songs from the musical, Born to Lead and The Pitch, which highlight the game theory problem at hand.

The Allies wanted to invade Sicily and get the Germans to believe they were invading elsewhere. So what might this problem look like?

Working backwards, the Germans can either believe the Allies or not, and the Allies could either lie or not. Naturally, they don’t know what each other is doing.* So when when the Germans receive information, how should they interpret it? Is it a lie by the Allies, or something to be trusted? And, what are the payoffs in the game?

For more on this game, watch the video below!

* Technically, for those who’ve taken game theory, you would know that the tree diagram should have an information set. Why? the Germans don’t know whether the Allies have lied when making the decision on whether to trust or not.