If you just look at how things work in most societies now and throughout history and use the model of 'the purpose of a system is what it does', then you could

If you just look at how things work in most societies now and throughout history and use the model of 'the purpose of a system is what it does', then you could surmise that the the purpose of society/nation is to make sure the top 0.01% of people have amazing lives. Everything else is just an consumable input to achieve that goal.