Research on the political consequences of social movements has recently accelerated. We take stock of this research with a focus on movements in democratic polities and the United States in comparative and historical perspective. Although most studies demonstrate the influence of the largest movements, this research has not addressed how much movements matter. As for the conditions under which movements matter, scholars have been revising their initial hypotheses that the strategies, organizational forms, and political contexts that aid mobilization also aid in gaining and exerting political influence. Scholars are exploring alternative arguments about the productivity of different actions and characteristics of movements and movement organizations in the varied political contexts and institutional settings they face. Researchers are also employing more innovative research designs to appraise these more complex arguments. Scholarship will advance best if scholars continue to think through the interactions between strategies, organizations, and contexts; address movement influences on processes in institutional politics beyond the agenda-setting stage; situate case studies in comparative and historical perspective; and make more comparisons across movements and issues.

S cholars have increasingly turned their attention to the consequences of social movements (cf. Zald 1988 andAmenta andCaren 2004). Much of this work has focused on the external consequences of movements, especially those relating to states and struggles over legislation. Despite this work, one reviewer (Giugni 2004) recently argued that our knowledge accumulation on the subject has thus far been minor. Others (McAdam 1999;Zald 2000) argue that the political process and resource mobilization models do not help to explain the consequences of these movements. Other reviewers (Burstein and Linton 2002) claim that quantitative analyses in this area have frequently been misspecified and that when public opinion is taken into account challengers are found to have little direct influence on state-related outcomes.In this paper, we seek to contribute to this debate by elaborating and appraising a political mediation theory of social movement consequences (Piven and This article elaborates a political mediation theory of the impact of social movements on states and policy, positing that the influence of mobilization and specific strategies of collective action depends on specified political contexts and the type of influence sought. Examining the influence of the U.S. old-age pension movement, which involved millions of people, this article appraises the mediation model using state-level data from the 1930s and 1940s on Old Age Assistance-the main support for the aged at the time-and a Senate vote for generous senior citizens' pensions in 1939. Our models control for other potential influences, notably public opinion, which is often ignored in empirical studies and sometimes claimed to be responsible for causal influence mistakenly attributed to challengers. We employ pooled cross-sectional and time series analyses and fuzzy set qualitative comparative analysis (FSQCA), which is especially suited to appraising the combinational expectations of the political mediation model. Both sets of analyses show that the pension movement was directly influential on the outcomes and provide support for the political mediation arguments.

During the Depression, the Townsend movement enjoyed varied success in seeking pensions for the aged. Social-movement models predict that success depends on the mobilization of resources or on collective action. Other theories predict that economic or political conditions cause the emergence of movements and changes in public spending. The political mediation model used here holds that, to succeed, a movement must reinforce political action with strong organization of members under favorable political conditions. This article defines "success" and employs various analytical and empirical strategies, including qualitative comparative analysis on statelevel data, to appraise the models. Although each perspective has some support, the political mediation model offers the best explanation of the patterns of successes. The state and the political party system determine whether mobilization and action benefit a constituency and win acceptance for a movement organization.Perhaps more than any other social protest movement of the Great Depression, the insurgency of the aged led by Francis E. Townsend has been credited with transforming public social provision in the United ' For comments, criticisms, aid, and advice, we thank

Comparative social scientists have developed various arguments about the determinants of social policies, especially those connected with twentiethcentury "welfare states." Structure-functionalists argue that the social policies of modem nations necessarily converge due to an underlying logic of industrialism, while neo-Marxists treat such policies as state responses to the social reproduction requirements of advanced capitalism. Yet most students of social policies are more attuned to history and politics. Concentrating on two dozen or fewer industrial capitalist democracies, many scholars have explored the alternative ways in which democratic political processes have helped to create programs and expand social expenditures. For a fuller range of nations past and present, scholars have also asked how ties to the world-economy