'When the division of labour was so little developed that every homestead produced all that it needed, it mattered nothing if part of the community was cut off from the world for weeks and months at a time. All the neighbours of a village or homestead might be slain or harassed, and no inconvenience resulted. But if to-day an English county is by a general railroad strike cut off for so much as forty-eight hours from the rest of the economic organism, we know that whole sections of its population are threatened with famine. If in the time of the Danes England could by some magic have killed all foreigners, she would presumably have been the better off. If she could do the same thing to-day half her population would starve to death. If on one side of the frontier a community is, say, wheat-producing, and on the other coal-producing, each is dependent for its very existence on the fact of the other being able to carry on its labour. The miner cannot in a week set to and grow a crop of wheat; the farmer must wait for his wheat to grow, and must meantime feed his family and dependents. The exchange involved here must go on, and each party have fair expectation that he will in due course be able to reap the fruits of his labour, or both starve; and that exchange, that expectation, is merely the expression in its simplest form of commerce and credit; and the interdependence here indicated has, by the countless developments of rapid communication, reached such a condition of complexity that the interference with any given operation affects not merely the parties directly involved, but numberless others having at first sight no connection therewith.