A new Japanese prime minister revives spectre of revolving door leadership

On 27 September, in a nail-biting finish, Shigeru Ishiba won Japan’s ruling Liberal Democratic Party’s presidency, defeating his nearest rival, Sanae Takaichi, in a run-off as there was no clear winner in the first round with nine candidates racing. Ishiba is sure to be designated Japan’s new prime minister on 1 October, as the LDP holds a majority in the Diet, Japan’s parliament.

With his sinking popularity amid financial scandals, a stagnant economy, and the yen on a slippery slope, in August, Prime Minister Kishida read the writings on the wall and announced he would step down and not seek the party presidency at the end of his three-year term.  It opened the floodgate to a record number of candidates vying for the position, making it the most unpredictable election as party factions and their leaders are in disarray.

Of the nine candidates, polls showed three consistently leading the pack. At the beginning of the race, the two favourites were Shinjiro Koizumi, a dynastic politician and former environment minister representing generational change, and former LDP Secretary-General Shigeru Ishiba, a member of the party old guard and a moderate with ministerial experience.  The third was right-wing female conservative Sanae Takaichi, an incumbent economic security minister and a protégé of the late Shinzo Abe.

A mid-September poll showed Ishiba – popular with LDP members, but less so with MPs – in the lead and Koizumi trailing.  Another poll showed Sanae Takaichi emerging as a serious competitor, suggesting she was the most favoured candidate, leaving Ishiba as number two and Koizumi far behind as number three.

Unlike many Westminster systems where leaders are elected in party rooms, Japan’s LDP follows a popular democratic process. The election system for choosing a leader is complex. The LDP president is elected for three years. A candidate must secure the endorsement of at least 20 LDP parliamentarians to run. LDP parliamentarians and more than one million rank-and-file LDP members from the 47 prefectural branches vote.

A run-off is held between the two top candidates if no candidate receives a clear majority in the first round. In the run-off, all LDP parliamentarians plus one representative from each of the 47 prefectures vote, tilting the vote in favour of parliamentarians. Ishiba received 154 votes, while Takaichi 181 in the first round. Since no candidate received a clear majority, in the runoff, Ishiba won 215 votes and Takaichi 194.

So, what does the election tell us about Japanese politics? First, the LDP, which has ruled Japan for all but four years since 1955, retains a commanding position. As soon as the new leader is elected through a party vote, it becomes inevitable for the president to be endorsed as prime minister. The strength of the LDP also arises from the weaknesses of the opposition, which remains divided and fragmented, unable to mount a credible challenge. The largest opposition party is the Constitutional Democratic Party, which has 99 seats in the 465-member House of Representatives, Japan’s lower house, while the LDP has 258 members. Polls show the LDP remains the preferred party with the support of 30% of voters and the largest opposition party trailing on 5%.

But it is essential the new prime minister restores public trust in the LDP and reinvigorates the economy. Kishida’s inability to tackle the financial scandal plaguing the party was the last straw that broke his back. Corruption is endemic in the LDP. It is common for prime ministers and ministers to step down, offering apologies, when a large scandal erupts publicly, while the party promises to clean up its act. It will test whether Ishiba can break this cycle and make politics more transparent.

On foreign policy, the key challenge for Ishiba will be to establish a strong relationship with a new president in the White House, with that task considerably more arduous should Donald Trump beat Kamala Harris in November. The continuity of the US commitment to Japan’s security and broader role in the Indo-Pacific is crucial for Japan due to its limited military role and dependence on the US nuclear umbrella. There is a sense of nervousness in Tokyo, as in many other capitals, about the new administration in Washington.

Almost every LDP leadership candidate noted the China challenge in their campaign speeches, albeit some without naming China. However, there was no consensus about how to deal with it. Some suggested nuclear-powered submarines for Japan to deter China from entering Japanese waters. Others favoured removing Japan’s three non-nuclear principles, while others preferred diplomacy and security networking with like-minded countries. Ishiba suggested building a NATO-like collective security arrangement for Asia. When asked about his Asian NATO at the press conference after his election, he named US Asian allies and Quad members, as potential partners. This might be a pie in the sky.

Still, Ishiba's strengths are in the defence and security area, and he is often called a military geek (gunji otaku) because he was twice the defence head and has written books on the subject. Japan does face significant security challenges that will require deft handling - the China-Russia “no limits” partnership and the deepening Russia-China-North Korea axis weigh heavily on the security outlook.  Japan regularly experiences incursions of its airspace and territorial waters. The Japanese Maritime Self-Defence Force recently sent a frigate through the Taiwan Strait for the first time, asserting its right to freedom of navigation, raising the strategic temperature in the region. How Ishiba responds to such security challenges will be watched closely. Yet, beyond an unlikely new security pact, what changes he will propose to defence and security policy is unclear.

At home, Ishiba will need to improve the LDP’s tarnished image in the electorate and turnaround the polls before the next lower house election, due by October 2025, but set to be held on 27 October this year. Similarly, in mid-2025, the three-yearly election of the upper house is due, and Ishiba must lead the party to a decent victory. If he falters, it won't be a surprise to see a return to the era of a revolving door prime ministership. Following Abe’s long premiership, the average was two years in office between Suga and Kishida. Japan and the world expect a stable government in Tokyo.

Purnendra Jain is an emeritus professor in the Department of Asian Studies at the University of Adelaide.