Assuming rationality or optimal play is not good way to think of real world actions. You only need three things for something like this to happen. 1. One side

Assuming rationality or optimal play is not good way to think of real world actions. You only need three things for something like this to happen. 1. One side thinks[1] that it will hurt the other side more than it does to itself. 2. Politically it can handle/sell the cost of such an action. 3. There is a leader who is ready to execute it as his agenda. [1] Only have to think so, it doesn't have to even be true.