The first and most far-reaching cause, as illustrated by the stove molders, was the competition of the products of different localities side by side in the same market. Stoves manufactured in Albany, New York, were now displayed in St. Louis by the side of stoves made in Detroit. No longer could the molder in Albany be indifferent to the fate of his fellow craftsman in Louisville. With the molders the nationalization of the organization was destined to proceed to its utmost length. In order that union conditions should be maintained even in the best organized centers, it became necessary to equalize competitive conditions in the various localities. That led to a well-knit national organization to control working conditions, trade rules, and strikes. In other trades, where the competitive area of the product was still restricted to the locality, the paramount nationalizing influence was a more intensive competition for employment between migratory out-of-town journeymen and the locally organized mechanics. This describes the situation in the printing trade, where the bulk of work was newspaper and not book and job printing. Accordingly, the printers did not need to entrust their national officers with anything more than the control of the traveling journeymen and the result was that the local unions remained practically independent. The third cause of concerted national action in a trade union was the organization of employers. Where the power of a local union began to be threatened by an employers' association, the next logical step was to combine in a national union. The fourth cause was the application of machinery and the introduction of division of labor, which split up the established trades and laid industry open to invasion by "green hands." The shoemaking industry, which during the sixties had reached the factory stage, illustrates this in a most striking manner. Few other industries experienced anything like a similar change during this period. Of course, none of the causes of nationalization here enumerated operated in entire isolation. In some trades one cause, in other trades other causes, had the predominating influence. Consequently, in some trades the national union resembled an agglomeration of loosely allied states, each one reserving the right to engage in independent action and expecting from its allies no more than a benevolent neutrality. In other trades, on the contrary, the national union was supreme in declaring industrial war and in making peace, and even claimed absolute right to formulate the civil laws of the trade for times of industrial peace.