No free society, let alone a libertarian one, can long survive if it actively welcomes those who would undermine its institution and culture. Such tolerance is the Achilles heel of open societies, and why they all eventually are undermined by nefarious forces, banksters, gangsters, communists, neocons, theocons, etc. Until a method is worked out for preserving freedom while maintaining openness and tolerance for diversity, open-border libertarians are never going to be taken seriously in politics. We are today, exactly in the situation we are in politically and financially, due to the mass importation of communists, anarchists, Trotskyites, Keynesians, Marxists, Maoists, monarchists, neo-feudalists, religious dogmatists, and so forth, as laborers for big business during the industrial revolution. None of these people had any respect nor commitment for the founding classical liberal or Unitarian values of the nation, and they promptly set about remaking America into the fouled up countries they had left behind.