Government is not, as some people like to say, a necessary evil; it is not an evil, but a means, the only means available to make peaceful human coexistence possible. But it is the opposite of liberty. It is beating, imprisoning, hanging. Whatever a government does it is ultimately supported by the actions of armed constables. If the government operates a school or a hospital, the funds required are collected by taxes, i.e., by payments exacted from the citizens. —Ludwig von Mises

Observably, a government dedicated to freedom needs a portion of a person’s possessions (money) to protect people and their property. Hence, government exercises its coercive power to tax.