Is providing for the common good a responsibility or a superfluous act of compassion?
Act One: Self-interest
Providing for the common good is a self-interested action for those who govern and for those who have prosperity. What happens to the leader who says, "Let them eat cake!" when the people are starving in the streets? Mm-hmm. Europeans still scream, "Off with their heads!" when education costs rise and labor benefits fall. Since the beginning of time leaders have understood that they have to provide adequate infrastructure and services to their people or their people will revolt. Providing for the common good is part of the process of distributing surplus value to sustain a nations power and wealth, and whatever conservative politicians will tell you in America today, that is exactly what governments do...that is what power is for...distributing wealth (and for distributing power itself).
This 'protection' from government is a bargain, as in: an agreement between parties settling what each gives or receives in a transaction between them or what course of action or policy each pursues in respect to the other (Webster). It is a bargain between protection and wealth extraction. The government needs resources for armies, infrastructure, maintaining economic viability, and distributing goods (especially food). The government takes those resources from the people, mostly in the form of taxes, but also, by conscription.
Historically, governments have gotten the bulk of their taxes from business, which is why business and government are so cozy, and have always been. Kings would offer protection to trading ships in exchange for treasures. Without that treasure the government would fall, and without protection the business man would be pillaged. I think we have a structure in America that can break that antiquated conflict of interest, as the favored business interest is not always the best interest for the country.
As for the people, historically, governments would take food and men from them to fuel armies and supply the courts. In return the people received protection from invading armies. People also expected to be guarded against famine and crisis and otherwise facilitated a good quality of life relative to the Leader's abilities.
Today, the government takes resources mostly in the form of taxes, though in the case of the draft, also conscription. We pay taxes for protection. Protection, in our case, of life, liberty, and the pursuit of happiness. Protection of our private property. Protection of justice. Protection through our constitution, our representatives, our laws and our courts...for a civil society...for a mutually assured stability.