The race to become Japan’s next prime minister in 2025 – the Liberal Democratic Party’s presidential race – was Koizumi Shinjiro’s to lose. Polls and pre-election gatherings among Diet members indicated that he was the overwhelming favorite to secure the support of Diet members and outperform Takaichi Sanae, who remained popular among the grassroots conservative base of the Liberal Democratic Party.
Before the LDP presidential election, Koizumi’s patron, Suga Yoshihide, had begun reaching out to Nippon Ishin no Kai to coordinate a new coalition that would provide the Koizumi administration with a working majority in both houses of the Diet. There were even reports that members of his campaign team were holding a ”celebratory party” the night before the ultimate result was to be called, treating Koizumi’s victory as an absolute certainty.
However, things did not turn out as expected for Koizumi. He significantly underperformed among rank-and-file members and was defeated by Takaichi, the most popular candidate among the LDP’s core supporters. Takaichi convinced Diet members that she could turn the tide for the party and reclaim its conservative edge – which had seemed to be waning due to a right-wing revolt against a party perceived to be distancing itself from them.
One immediate cause of this turn of events was the scandal surrounding the Koizumi campaign team’s dissemination of pro-Koizumi comments – and ones disparaging his opponents – during online streaming, which dented his authenticity as a candidate. But the critical issue that thwarted his victory not only in 2025 but also in 2024, when he first sought the premiership, was his perceived inexperience. Koizumi’s reliance on prepared remarks during public debates likely highlighted concerns among party members that he needed more seasoning to be a trustworthy leader in a time of trial. The surge of fellow candidate Hayashi Yoshimasa – an experienced administrator who finished third in the race, behind Takaichi and Koizumi respectively – attested to the importance of experience as a deciding factor in selecting a party leader within the LDP.
Despite coming in second place, Koizumi’s loss was not entirely a step back. In fact, his appointment as minister of defense – a high-profile position and especially important in a Takaichi administration where defense policy is a priority – seems to have changed his persona overnight.
Since Koizumi landed in his new role, he – and the Ministry of Defense as a whole – has notably increased public outreach through various media – a goal Koizumi set out when he assumed the job. Koizumi’s appearances in long-form online programs, and the public announcements of foreign military activities surrounding Japan, are part of his efforts to increase transparency into the ministry’s work, and also raise awareness among the public of “the most severe and complex security environment since the end of World War II” that Japan faces. These efforts have given a spotlight to Koizumi as Takaichi’s spokesperson for her resolute defense policy – and, in the process, overhauled public perceptions of Koizumi.
Even his political opponents – especially those more attuned to online discourse – have picked up on this shift in mood. Shinba Kazuya, the secretary-general of the Democratic Party for the People, whose daily press briefings have become popular online content in their own right, shared his observation that he sensed Koizumi was an “awakened man,” and praised his expertise on the Japanese Maritime Self-Defense Force, which is based in Koizumi’s electoral constituency. Hyakuta Naoki, the head of the Conservative Party of Japan, who has been a conservative influencer with a large following, also shared the increasingly prevailing view that Koizumi has indeed “awakened” since becoming head of the Defense Ministry.
The perceived “awakenedness” of Koizumi implies that the prevailing public image of him was different before his new job “changed” him. Before becoming defense minister, in the eyes of his critics, Koizumi was a prime minister’s son born with a silver spoon, defined by his meandering remarks and a slightly liberal bent in his political leanings – a reason for his lukewarm relationship with the conservative base of his party. However, the popularity of Takaichi, and Koizumi’s advocacy of her government policies, have transformed Koizumi’s persona and increased his credibility as a statesman – with additional benefits that could help him to be Takaichi’s eventual successor.
As Hyakuta’s observation highlights, the “awakened” Koizumi is being embraced by conservatives – a core constituency he failed to court in his previous bids for prime minister. This reception is largely a result of his association with Takaichi, a conservative darling, and an impression that he is tough on China, stemming from his public disclosure of China’s radar lock-on of Japanese jets.
An example of this conservative embrace could be seen in two Japanese right-wing magazines – Will and Hanada – which have recently featured Koizumi on their covers and included interviews between Koizumi and prominent conservative pundits. One of the interviewers, Sakurai Yoshiko, could not resist using the same popular refrain on her online program: she praised Koizumi, a guest on her show, saying he had “awakened” and become a completely different person since becoming defense minister. Koizumi agreed that people had been saying he had “awakened” a lot.
The irony of Koizumi is that he has been constantly underestimated and overestimated in equal measure by friend and foe alike. Koizumi entered the Diet at the age of 28, with little political experience beyond his observation of his father as prime minister. Yet less than a year later, he was already a popular surrogate for LDP candidates, treated as a political celebrity. While he chaired committees within the LDP and also in the Diet from a relatively young age – becoming the youngest male politician to serve as a Cabinet minister when he headed the Environment Ministry in 2019 – his youthful appearance seems to have continuously left him in deficit when it comes to credibility as a policymaker, a debt his actual experience has failed to repay.
His new role as defense minister has led his critics to realize he was fit for the job, but it’s also a post Koizumi was uniquely well suited for. He started his career as a think tank researcher in Washington D.C.; that plus his constituency work in an electoral district that hosts not only the MSDF but also the U.S. 7th Fleet had already well prepared him for the language and posture his current position demands.
The “awakening” of Koizumi Shinjiro is indicative of how a seemingly fixed notion of a politician can change through the amplifying power of online attention, attesting to the increasing political influence that social media can have over Japanese politics today. The conservative embrace of the “awakening” narrative also attests to their loyalty to Takaichi, give Koizumi’s role in her Cabinet. More broadly, Koizumi’s upgraded image shows how the threat posed by China is becoming a litmus test by which Japanese conservatives judge the trustworthiness of a politician.
While his “awakening” was thrust upon him rather than the product of his own conscious efforts, the new media environment has given Koizumi a gift he owes to Takaichi – a new persona tied to a new role that will only enhance his stature as the public grows increasingly cognizant of the security environment.
