Consider a game of mutually assured destruction played by two superpowers, country 1 and country 2. country 2 has precipitated an international incident. country 1 can either ignore the incident or escalate the crisis. if it ignores the incident the game ends and both countries receive a payoff of 0. it if escalates, then country 2 can either escalate further or back down. if it backs down, then the game ends, country 1 receives a payoff of 2, and country 2 receives a payoff of 2. if country 2 escalates further then 1 and 2 play a game where they move simultaneously. each has two strategies in this subgame: back down or doomsday. the payoffs in the subgame are as follows: find all subgame perfect nash equilibria of this game.