Sex in the US - a new Nash equilibrium

[timelets]

The US has moved into a new equilibrium where sex/marriage between two equal consenting partners, including teenagers above a certain age or gays, is the optimal strategy. To people who live or used to live in a patriarchal society this may feel weird but they will have to adapt. It's like driving in a foreign country: after some initial period of stress, tourists learn to drive on the "wrong" side of the road.

upd. There are several conditions that make the equilibrium work:
- Equal Protection Clause (legal aspect)
- Effective contraception (biological aspect)
- Discouragement of cheating (social aspect)
- Preference for monogamy (is this the same as the one above?)

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