The etymology of "republic" is the Latin phrase rei publicae, literally "public things." Some might say "So? Whatever government decides to involve itself with is a public thing." But, as Oliver Wendell Holmes and others have noted, the existence of "public things" clearly implies the existence of private things as well, or there would be no need for the qualifier.
The dividing line between the properly public and properly private spheres will never be drawn once and for all to everyone's satisfaction. However, the recognition that we should concede such a division, and attempt to establish it firmly, is central to republicanism. That's why republican concepts always include constitutional concepts as well; the whole point of a constitution is to put firm limits around the power of the State.
Decentralization and localism assist in maintaining republican orientation in many ways. In particular, people are more likely to constrain their neighbors' exercises of power than they are to act against Washington. The "political competition" evoked by localism is an excellent feedback mechanism that curbs the excesses of government. However, the core idea, the recognition that there exists a zone beyond which government power, no matter its intentions, may not go, is the beating heart of republican thought, the engine that drives the writing of constitutions and the exploration of the nature of rights and the greater good.
Freedom, Wealth, and Peace,
Francis W. Porretto
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