An Irrational Party of Rational Members

Abstract

This study presents a new explanation to a puzzle regarding the reluctance of the Japan Socialist Party (JSP) to moderate its hard-liner Marxist platform. The author does so by focusing on the preferences and strategies of individual JSP members, in contrast to previous studies that treat the party as a unitary actor. The author shows that Japan’s electoral system created a unique environment in which the electoral prospects for some JSP incumbents would be seriously jeopardized if their party increased its popular support. The analysis demonstrates that the degree of security JSP politicians had in retaining their own seats was a significant determinant in their attitudes toward a proposed policy moderation plan that was considered during a critical period in the early 1960s that could have increased support for the party.