It is one of the dominant features of our constitutional system that the nation, except for the regulation of interstate and foreign commerce, has debarred itself from the active and positive care of social and economic interests. The other great federated commonwealths of the world have more liberal provisions in this respect. Germany has assigned to the imperial power the whole subject of trade and industry; the Swiss constitution of 1874 mentions as subjects of federal legislation hours of labor and the care of health in factories; in Canada the Dominion is given residuary powers which cover the bulk of industrial legislation, and Australia by a wise provision allows any two or more of the states to refer to the federal parliament any matters to be regulated for the referring states jointly. The United States has by its constitution undertaken to safeguard individual right as an immunity from governmental oppression, but not as an immunity from private exploitation which falls short of reduction to practical servitude. Congress cannot enact protective measures for women in industry applicable to the nation at large. Its position is in this respect the same as with regard to child labor. It has been suggested that the United States might and should debar products manufactured by child labor from interstate or foreign commerce, and if this were practicable, women’s work might be controlled in the same way. Such a legislative contrivance would violate the spirit, if not the letter, of the constitution, and on that account would meet with strong and legitimate opposition. It is undoubtedly an anomaly, that our arbitrary and artificial state lines should stand in the way of such uniformity of industrial control as competitive industrial conditions may demand. A certain measure of unity may perhaps be achieved by the hitherto untried method of legislative agreements between several states, subject to the consent of Congress. But under the limitations of state constitutions, such unity would be a precarious thing, and its possibility has hardly been discussed.