WHY SOCIAL-MOVEMENT SYMPATHIZERS DONT PARTICIPATE - EROSION AND NONCONVERSION OF SUPPORT

Social movement organizations face the challenge of converting action preparedness into action participation, and accordingly, they must dea l with factors that lead to nonparticipation. We identify two routes t o nonparticipation-''nonconversion'' and ''erosion.'' Nonconversion re fers to a movement's failure to transform sympathizers into active par ticipants. Erosion refers to the loss of sympathizers. We provide a th eoretical framework for explaining nonconversion and erosion and apply it to a longitudinal study of a mobilization campaign of the Dutch Pe ace Movement: the People's Petition against cruise missiles. Data came from telephone interviews we conducted among random samples (N = 224) from the populations of four communities before and after the campaig n (in May and November 1985). We use binomial logistic regression anal yses to test several explanations of nonconversion and erosion. Factor s that led to erosion were moderate action preparedness at the beginni ng of the campaign, declining preparedness during the campaign, and a social environment perceived by participants as becoming less and less supportive. Factors that led to nonconversion were moderate but stabl e action preparedness combined with the presence of barriers to action and an indifferent social environment. Results are discussed and rela ted to social movement literature.