| Traditional literature tells us that in Japan, prime ministers only play a limited role in policy-making. Any significant policy changes must proceed through the party organs and first obtain party approval. Contrary to expectations, however, Japan's last prime minister, Junichiro Koizumi, dominated the agenda of policy debates. Despite strong opposition from within his own party, he even successfully passed controversial bills such as postal privatization. This study asks whether the shift from a party-centered to a Cabinet-centered policy-making process comes as a result of the actions of a single individual (Koizumi) or, rather, is driven mainly by deeper institutional changes.;I find that while individuals matter, institutional changes have primary explanatory power. The key institutional changes are respectively administrative reforms, political reforms, and LDP electoral rules changes. All became effective before or at the same time as Koizumi became the prime minister. These institutional changes had been proposed several times in the past without success and they were finally enacted by the LDP in response to the changing circumstances that the LDP was facing so that it could continue to survive politically. Administrative Reforms explicitly strengthened the role of the prime minister and the function of the Cabinet by clarifying the prime minister's dominance at Cabinet meetings, and granting more authority and providing more staff to support the prime minister. Political reforms were designed to promote party-based competition and weaken factional influence, implicitly elevating the party executive's influence. Last, LDP presidential electoral rule changes allowed party members to elect their leader directly instead of factions in the past. The new rules increase the autonomy of LDP presidents over party heavyweights.;Unlike other scholars who tend to examine the impacts of a single institutional change, I argue that each change alone cannot explain growing concentration of power in the hands of the prime minister. Each change by itself might not have been significant. However, because they happened one after another, they accumulated and generated a sea change that fundamentally altered the nature of Japanese politics. In other words, regardless of how minor they are, institutional changes can have massive interactive effects when they occur in a series. |
