Let me mention Graham Allison and Philip Zelikow's excellent book Essence of Decision: Explaining the Cuban Missile Crisis (2nd ed. 1999) here. The thesis of the book is that it's often a bad idea to try to understand the actions of countries by treating them as rational actors, and it illustrates it by three takes on the Cuban missile crisis.

In the first chapter it uses the rational actor model and asks about each event "what was the Soviet Union trying to do here". It turns out to be extremely puzzling: for instance they shot down a recognizance plane in the last few days when they seemingly could not gain anything by such a provocation, they were extremely inconsistent with their camoflage (did they want to be discovered?), and they had weird reloading arrangements (seemingly signalling that they intended the missiles to be used for a first strike).

Then in the next two chapters, the book dissolves these mysteries by instead considering the actions as flowing from different institutions or individual decision-makers within the Soviet Union. For instance, two different organizations were involved in managing camouflage, and the reloading arrangements were standard operating procedure for the Rocket Forces (and made sense for continental sites). And the U2 shoot-down? Well, the air defense forces had standing orders to shoot down American planes, but they were not able to get their radar system up and running until the last day of the crisis...

If they have standing orders like "If you're shot at, shoot back" then there's still potential for trouble. I think that, in the recent incident, South Korea was holding military exercises in or around places that North Korea claims are part of its territory (claims which the rest of the world doesn't recognize), and the exercises included things like shooting at targets. So it doesn't seem that weird for some North Korean guy to go "OMG, they're shooting at us!" when the South Korea military is nearby and shooting.