It is not, however, open to much doubt that the Department was not a very successful custodian of the trade autonomy principle. Jurisdictional disputes are caused either by technical changes, which play havoc with official "jurisdiction," or else by a plain desire on the part of the stronger union to encroach upon the province of the weaker one. When the former was the case and the struggle happened to be between unions of equal strength and influence, it generally terminated in a compromise. When, however, the combatants were two unions of unequal strength, the doctrine of the supremacy of the "basic" unions was generally made to prevail in the end. Such was the outcome of the struggle between the carpenters and joiners on the one side and the wood workers on the other and also between the plumbers and steam fitters. In each case it ended in the forced amalgamation of the weaker union with the stronger one, upon the principle that there must be only one union in each "basic" trade. In the case of the steam fitters, which was settled at the convention at Rochester in 1912, the Federation gave what might be interpreted as an official sanction of the new doctrine of one union in a "basic" trade. Notwithstanding these official lapses from the principle of craft autonomy, the socialist industrialists[81] are still compelled to abide by the letter and the spirit of craft autonomy. The effect of such a policy on the coming American industrialism may be as follows: The future development of the "department" may enable the strong "basic" unions to undertake concerted action against employers, while each retains its own autonomy. Such indeed is the notable "concerted movement" of the railway brotherhoods, which since 1907 has begun to set a type for craft industrialism. It is also probable that the majority of the craft unions will sufficiently depart from a rigid craft standard for membership to include helpers and unskilled workers working alongside the craftsmen.