. @casssunstein lays out the prisoner's dilemma that Democrats find themselves in with the GOP, but doesn't quite lay out what game theory has taught us about the best way to proceed: Generous Tit-for-Tat (or Tit-for-Tat with Forgiveness). 1/9 https://www.bloomberg.com/opinion/articles/2020-10-27/what-democrats-playbook-might-look-like-in-2021

This @Radiolab episode describes the 1960s tournament with computer programs vying with one another in a version of a Cuban Missile crisis to see if they could avoid escalating to Armageddon. Here were the algorithms. 2/9 https://www.wnycstudios.org/podcasts/radiolab/segments/104010-one-good-deed-deserves-another

Massive Retaliatory Strike: Cooperate until the first attack, then retaliate the rest of the time. Result: mostly Armageddon. 3/9

Tester: Start with an attack. Back off if there's retaliation cooperate for a while. Then attack again. Tester is designed to see how much it can get away with.

If Tester plays Massive Retaliatory Strike, the result is Armageddon. 4/9

Jesus: Always be nice.

Lucifer: Always attack.

If Lucifer plays Jesus, evil wins. 5/9

Tit-for-Tat was the winning algorithm: 2 lines of code. 1) Start with being nice. 2) Do whatever the other side did on the last move. It retaliates only once.

That elicits cooperation from anyone inclined to cooperate, but it doesn't take any guff. 6/9

When playing against Jesus, cooperation prevails for all 200 rounds of the tournament.

Against Lucifer, Tit-for-Tat plays solid defense.

The weakness is the echoing still results in Armageddon. 7/9

The solution was Generous Tit-for-Tat (or sometimes called Tit-for-Tat with Forgiveness). Every tenth or so time, it doesn't retaliate. It offers cooperation. It leaves the door open to not simply screwing one another. 8/9

I don't know if the GOP playbook is Lucifer, Tester, or Massive Retaliatory Strike.

But the one way out is for the Blue playbook to Tit-for-Tat with Forgiveness. It requires unapologetic retaliation for dismantling norms, but still offers periodic tests of cooperation. 9/9