War is the essence of life. Limited resources means any growing system inevitably hits this (carrying) limit. Sooner or later, there are no more unclaimed resources available and you have to start competing with others for access to the resources. Mutation and evolution follows. The only alternative is to open up more resources (like the Haber–Bosch process did) but that's just postponing the inevitable. The amount of (useful) matter and energy in the universe is both finite and decreasing.