I have been in countries at war, like Congo, and life there was the simplest thing you could have.
In fact, all the complexity appears when there is peace. People do not save or study or anything secondary when there is war.
Are you going to study when you don't know where your family is? When your mother or sister or daughter has been raped and you have to protect her for being raped or killed? When they go after you because you abandoned guerrilla (or the army)?
You make a simple mistake(like looking weak, with no friends or too smart) and you die, it was as simple as that. A kid without beard with an automatic gun does not like or respect you? You are dead.
People at war, they need something, they take it(with automatic weapons). Super simple.
In China things were also super simple. When I was there a biker was hit by a car and died. Nobody gave a dam. Cars were circulating as usual around the dead person. It was the most brutal thing I ever saw in my life, including Congo, in Congo people cared more about each other.
It is the developed world that is complex and sophisticated. People work for abstract things like "career", "pensions", "tenure" or even paper money that are promises that don't really exist as real things but really are symbols of trust in the society.
BTW you feel alive living at the moment and I personally miss some part of that, even when I was risking my life.