Creation of compulsory social insurance presented both a danger and an opportunity to France's mutual movement. Danger arose from the possibility that legislators would prefer a centralized and state-administered regime. This scenario would promptly marginalize most mutual societies. For if participation in a state-run system became compulsory and the coverage therefrom sufficient, the appeal of private mutual aid would surely diminish. On the other hand, if the new law placed mutual societies at its center by simply mandating mutual membership, social insurance could present a boon to the mutual movement. Yet this latter possibility, which would appear to be windfall gain, confronted mutual leaders with a doctrinal dilemma. The movement had long embraced voluntarism and rejected state intervention that sought to require individual social protection. Many mutual leaders viewed state-coercion, even if it would increase mutual membership, as an unacceptable adulteration of their principles. They resisted all social insurance legislation and opposed their fellows who cooperated with parliamentary leaders. Indeed, the 1920s debate over national social insurance instigated a fight for control of the mutual movement's leading national association, the Fédération Nationale de la Mutualité Française (FNMF). In opposition to traditionalists, who resisted any form of state mandates, stood a group of what may be termed realists. Realists argued that state-mandated social insurance, if correctly crafted, could save the mutual movement from a peril that loomed just as ominously as a total state takeover of social welfare.