JUST UNDER one year has passed since Suga Yoshihide became Japan’s prime minister. It was enough time for him to lose the confidence of both the public and his colleagues in the ruling Liberal Democratic Party (LDP). On September 3rd he bowed out of the LDP leadership race that will take place later this month; his replacement will immediately become prime minister. Despite his flailing approval ratings, Mr Suga’s decision caught allies and critics alike by surprise. It seems to have been precipitated by two crucial missteps in the past week—threats to reshuffle the LDP’s leadership and to dissolve the Diet ahead of schedule—that left him too isolated within the party to continue. His departure leaves the LDP leadership race—and, by extension, Japan’s political future—in flux.

The LDP will vote for a new president on September 29th. The winner will lead the party in lower-house elections that must be held by late November. A handful of potential contenders stand out. Kishida Fumio, a former foreign minister, had already declared his intention to run against Mr Suga. He has good relationships within the party, but limited popular support. Kono Taro, a former foreign and defence minister and the current vaccine czar, now seems likely to enter the race too. Mr Kono, who is American-educated, social-media savvy, and, at 58, on the younger side by Japanese standards, has long been a public favourite, but his reputation as a maverick puts off many in the LDP’s old guard.

Ishiba Shigeru, another former defence minister, may enter the fray as well. He too has sizable public support but little amongst colleagues, and has failed to break through in previous LDP elections. Seiko Noda and Takaichi Sanae, two former internal-affairs ministers, both hope to become Japan’s first female prime minister, but may struggle to secure the backing of 20 lawmakers that they need to run. Some whisper that Abe Shinzo, who preceded Mr Suga as prime minister, may mount another comeback, though that seems unlikely given lingering concerns about the scandals and health issues that begat his resignation last year.

None of the main candidates represents radical change in policy terms. All are staunch supporters of the alliance with America, and favour shoring up Japan’s own defences in the face of Chinese expansionism. No one will move to reverse the Bank of Japan’s loose monetary policy or to impose fiscal austerity. Yet there are subtle differences. Mr Kishida favours more fiscal stimulus and more support for the economically vulnerable than Mr Suga did; he has pledged a big economic stimulus package to counteract the pandemic. Mr Kono has taken some heterodox stances in the past, such as phasing out the use of nuclear power, and would probably put more political capital into Japan’s shift toward renewable energy in the pursuit of carbon neutrality. Mr Ishiba might focus more on measures to revive Japan’s rural regions. Ms Takaichi has positioned herself as a face of the party’s right wing, taking up the cause of revising Japan’s post-war constitution.

As ever when it comes to LDP politics, the contest hinges mostly on personalities and internal power games. The main fault lines this time around are stylistic and generational. In many ways, the choice is shaping up to be one between a predictable, old-style party man, such as Mr Kishida, and a younger, more charismatic leader, such as Mr Kono. The outcome will depend on backroom wheeling-and-dealing and inter-factional horse-trading, but also on how worried the party leadership is about the looming Diet elections and how much influence younger backbenchers can exert. Before Mr Abe’s eight-year-long premiership, Japan had cycled through six prime ministers in six years (including Mr Abe’s own failed first term in 2007). There is a risk that Mr Suga’s resignation will precipitate a similar spell of turmoil at the top of Japanese politics. But it may also open the door to a new era. The only certainty is that Japan has entered a period of uncertainty.