Abstract
This article provides a theoretical and empirical cross-national analysis of the relationship between two composite concepts: left-wing mobilization (entailing consideration of the degree of social democratic party rule, left-wing party opposition, and trade union strength) and socioeconomic equality. A typology of this latter concept is presented that focuses upon four dimensions of equality: meritocratic (equality of opportunity), welfarist (ethos of the modern welfare state), emancipatory (socio-proportional equality for sexual, ethnic, and racial groups), and egalitarian (equality of income distribution). After consideration of the theoretical literature on the impact of the partisan composition of government (as well as the role of opposition and trade union forces) upon the degree of socioeconomic equality, hypotheses are derived to test empirically this relationship for the advanced capitalist states of Western Europe, North America, and the Pacific during the postwar era. The findings lend credence to a view (termed in this article the Constrained Socialism school of thought) that perceives severe politico-economic constraints in the ability to increase substantially those dimensions of socioeconomic equality that are not highly compatible with the interests of advanced capitalism.