How come war is a trillion dollar industry in the world (the largest industry) when it would only take a few billion dollars to bring green, sustainiable energy to the poorest, war-torn countries in Africa?

Is it within human nature to be destructive of the inherent capacity we have developed for advancement and civilization? An existential imperfection which makes us destroy our own humanity? Why are we so apathetic about our survival but strongly hell-bent on our self destruction?