Activism depends on more than just idealism. It is not enough that people be attitudinally inclined toward activism. There must also exist formal organizations or informal social networks that structure and sustain collective action. The volunteers were not appreciably more committed to Freedom Summer than the no-shows. Their close ties to the project, however, left them in a better position to act on their commitment. Those volunteers who remain active today are distinguished from those who are not by virtue of their stronger organizational affiliations and continued ties to other activists. Attitudes dispose people to action; social structures enable them to act on these dispositions. Thus by sustaining political organizations and maintaining links to others, the volunteers are preserving the social contexts out of which movements have typically emerged.
McAdam, Doug. Freedom Summer. Oxford University Press; Oxford. 1988. p. 237