I've been reading Resilience: Why Things Bounce Back by Andrew Zolli and Ann Marie Healy (NY: Free Press, 2012 ISBN 978-1-4516-8380-6) and came across a description of a variation of the Tit for Tat strategy in the Prisoner's Dilemma game called Discriminatory Tit for Tat (DTFT) which seems to describe the recent and current political impasse in Washington DC.
They [game theorists Steve Rytina and David L. Morgan] watched what happened when members of each tribe followed a variant called Discriminatory Tit for Tat (DFTFT), which is just like Tit for Tat except when dealing with someone of a different-color group. A Red will always defect with a Blue, and vice versa.
A Red will cooperate with a Red and a Blue will cooperate with a Blue but Reds and Blues will never cooperate with each. Sound familiar?
What piqued my interest even more is their finding:
Rytina and Morgan demonstrated that the DTFT game play is not only stable, it's all but intractable. In the early rounds, an individual who tries to play regular, color-blind Tit for Tat is worse off than one who defects with the out-group. Why? When a Red and Blue interact for the first time, even if the Blue contemplates cooperating (as in regular Tit for Tat), the Red player will almost certainly be playing DTFT and will defect. That means that the Blue player - only trying to start off nice - will get the sucker payoff and lose points.
DTFT is not a more successful strategy than regular Tit for Tat, which is better for long-term resilience, and tends to penalize the minority more than the majority (unless the majority continues to expect regular Tit for Tat no matter how many times it is faced with evidence to the contrary).
The problem with DTFT is in its insidious stability. Once it is entrenched, it punishes individual efforts to attempt cooperation across enemy lines.
I've emailed Steve Rytina to find out whether any game theorists have written about DTFT in relation to the present situation in DC or figured out a way out of its "insidious stability."