This study tests two propositions from Navarro's critique of the social capital literature: that social capital's importance has been exaggerated and that class-related political factors, absent from social epidemiology and public health, might be key determinants of population health. The authors estimate cross-sectional associations between economic inequality, working-class power, and social capital and life expectancy, self-rated health, low birth weight, and age- and cause-specific mortality in 16 wealthy countries. Of all the health outcomes, the five variables related to birth and infant survival and nonintentional injuries had the most consistent association with economic inequality and working-class power (in particular with strength of the welfare state) and, less so, with social capital indicators. Rates of low birth weight and infant deaths from all causes were lower in countries with more "left" (e.g., socialist, social democratic, labor) votes, more left members of parliament, more years of social democratic government, more women in government, and various indicators of strength of the welfare state, as well as low economic inequality, as measured in a variety of ways. Similar associations were observed for injury mortality, underscoring the crucial role of unions and labor parties in promoting workplace safety. Overall, social capital shows weaker associations with population health indicators than do economic inequality and working-class power. The popularity of social capital and exclusion of class-related political and welfare state indicators does not seem to be justified on empirical grounds.