This study analyzes the link between egalitarian ideals and the rise in party polarization in Congress. To demonstrate how philosophical differences over conceptions of fairness, equality, and justice help explain the recent growth in partisanship over the past few decades, I argue one overlooked explanatory factor which assists in capturing this ideological rift is noncontributory welfare spending. Recovering annual ideal point estimates between 1947 and 2018 that are comparable with annual federal spending, I use multivariate time series models and find convincing evidence which suggests welfare outlays have a strong short- and long-run effect on polarization. Moreover, analysis of the roll call record also shows when ideal point estimates are recovered by specific policy area, lawmakers exhibit higher levels of ideological separation on welfare compared to, among others, policies such as defense and transportation. Robustness checks confirm these findings also hold even when controlling for income inequality.
