Shigeru Ishiba on Liberal Democratic Party (LDP)

Shigeru Ishiba is a long-standing but often critical member of the Liberal Democratic Party (LDP) who eventually secured the party presidency and premiership in 2024 after numerous previous bids for leadership. Throughout his career, he has cultivated a reputation as a political maverick, willing to voice criticisms against his own party's dominant factions and policies, even while holding high-ranking positions within LDP governments. His path to the top was characterized by internal friction, as evidenced by his narrow victory in the 2024 LDP presidential election, which was dubbed "Ishibamania" by some observers due to the upset nature of his win.

Despite his long service and eventual leadership, his tenure as LDP President and Prime Minister was brief and marked by electoral failure, culminating in his resignation in September 2025 following the coalition losing its majority in the upper house election, a second major loss after the lower house defeat in 2024. His relationship with the party establishment has been complex; he was once a vocal critic of factionalism, yet he formed his own faction, the Suigetsukai, to pursue the leadership. His leadership style and moderate conservative positions also drew sharp criticism from the LDP's more conservative wing, illustrating a constant tension between his desire for reform and the party's traditional conservative base.