The battle over abortion in America is seemingly endless. The longstanding nature of the conflict is due in part to the ability of both the "pro-choice" or abortion rights movement and the "pro-life" or antiabortion countermovement to continue to organize support for many years. The pro-choice movement is particularly remarkable in that it has not only survived for more than twenty-five years, but it has grown stronger since achieving its greatest victory, legalization of abortion in 1973.
In this article I want to explain the longevity of the pro-choice movement by looking at both internal organizational changes in the movement and external changes in the political environment of the movement. I begin with a general discussion of these theoretical factors in the growth and maintenance of social movements. I then describe the history of the pro-choice movement in the United States, showing how these elements come into play. I conclude with a discussion of the lessons of this history for theories of social movements. 1
One explanation as to why particular social movements emerge and flourish at certain times and not others is that the political climate is more or less receptive at different times. A number of theorists argue that movements are most likely to arise when the "political-opportunity structure" is