A Modern Utopia Requires an Entire Planet

No less than a planet will serve the purpose of a modern Utopia. Time was when a mountain valley or an island seemed to promise sufficient isolation for a polity to maintain itself intact from outward force; the Republic of Plato stood armed ready for defensive war, and the New Atlantis and the Utopia of More in theory, like China and Japan through many centuries of effectual practice, held themselves isolated from intruders. Such late instances as Butler's satirical %u201CErewhon,%u201D and ...