Japan’s Snap Election: Implications for National Security Policy

Only three months after her victory in the race for Prime Minister, Sanae Takaichi suddenly called a snap election, presumably to increase her influence in the Diet while her approval rating was still high. In a stunning victory, her Liberal Democratic Party (LDP) won 316 of the 465 seats in the lower house, up from 198, for the biggest victory in postwar Japan. Including its coalition partner, the Japan Innovation Party, the ruling party won a total of 354 seats. Liberal forces, in particular the Centrist Reform Alliance (Chudo), recently formed by the merger of the Constitutional Democratic Party and Komeito, were completely defeated, seeing their seat totals fall from 170 to only 49.

The election clearly shaped Japan’s future security path. Earning more than a two-thirds supermajority, Takaichi will likely strengthen the country’s defense capability more rapidly and perhaps on a larger scale. It was also a favorable outcome for the Donald Trump administration, signaling that Japan would pursue security policies in line with the recently released National Defense Strategy (NDS), including “peace through strength” and more burden-sharing.

Japanese Public Opinion on Security Policy

One of the major reasons for the LDP’s landslide victory was the immense personal popularity of Takaichi, who, as the first female prime minister, is expected to bring a breath of fresh air to Japan’s old political system. She enjoys particularly strong support from young people. A December poll showed that Takaichi had approval ratings of 92.4 percent among those aged 18–29, 83.1 percent among those in their 30s, while still managing to secure nearly 78 percent support from voters in their 40s and 50s.

Although the economic policy and counter-inflation measures were the public’s top concerns amid perceptions of a stagnant economy, each party proposed relatively similar solutions for these problems, including tax cuts and cash handouts. If anything, the LDP’s proposed measure against rising prices, including the elimination of the consumption tax on food for two years, seemed less consumer-friendly than many other parties, and her enthusiasm for implementing those measures was also questioned. Therefore, it is unlikely that the LDP’s economic measures were particularly popular with voters.

Instead, the policy that most clearly divided the LDP and the left-wing parties was national security. The liberal forces, such as Chudo, the Japanese Communist Party, and Reiwa Shinsengumi, bitterly attacked Takaichi’s security policy, including her recent remarks on Taiwan, which have sharply increased the tensions with China, her subservient stance to the Trump administration, and her plans to expand military spending and revise the “three non-nuclear principles.” They claimed that Takaichi is ignoring Japan’s pacifist constitution and leading the country into war.

However, the election result suggests that this strategy has backfired, and the prime minister’s diplomacy and security policies are, in fact, supported by the majority of Japanese voters. A survey on those issues also found surprising cohort effects. While only 40 percent of those aged 70 and older supported her plans to expand the defense budget, 80 percent of Japanese aged 18 to 29 do. The election results show that Japanese voters support Takaichi’s hawkish “two-sword” strategy, which aims to strengthen security ties with the United States while expanding Japan’s self-defense capabilities.

Trump Administration’s Security Policy

During the campaign, Trump strongly endorsed Takaichi on his social media, praising her leadership and abilities, which Japan’s liberal parties fiercely criticized as interference in internal affairs. Trump’s pro-Takaichi stance is also evident in the administration’s consideration of treating her as a state guest on her first visit to the United States in the spring. This may be the Trump administration’s strategy to demonstrate a strong U.S.-Japan partnership and gain greater negotiating leverage during his April visit to China, but it is also good news for the Takaichi administration, both for advancing its China strategy and for maintaining domestic support on defense issues.

Japan’s security policy direction under the Takaichi administration will likely resonate with the recently released NDS as well, which appears to reflect a combination of traditional realism and Trump’s “America First” principles.

The NDS states that China is a priority for America’s national defense. It also emphasizes that China in the Indo-Pacific should be deterred “through strength, not confrontation.” Deterrence should be achieved by sustaining a strong denial defense and by improving collective defense with allies. Besides this realism-oriented strategy, burden-sharing is listed as one of the major strategic pillars in the NDS: “sensibly and prudently pressing and enabling U.S. allies and partners to take primary responsibility for defending against those other threats, with critical but more limited U.S. support.”

The NDS asserts that under the Trump administration, the United States has seen its allies “beginning to step up, especially in Europe and South Korea.” For the Takaichi administration, which has been strongly emphasizing close cooperation with the United States, it must be disturbing that Japan’s name has not been mentioned at all. As the Trump administration expects, this may put further pressure on Takaichi to improve Japan’s self-defense capability.

In her recent speech to the Diet, for example, Takaichi announced her proposal to review three defense documents this year, including the National Security Strategy (NSS), the National Defense Strategy (NDS), and the Defense Buildup Program (DBP). The security policies that Takaichi is keen to implement, such as promptly acquiring counterstrike capabilities, increasing defense spending, strengthening Japan’s defense industry, partially revising the three non-nuclear principles that prohibit nuclear weapons from being brought into Japan, and amending Article 9, are all aligned with the strategies outlined in the NDS.

Takaichi is eager to improve Japan’s defense capabilities based on the self-defense principle, which is supported not only by its coalition partner, the Japan Innovation Party, but also by some of the opposition parties rapidly gaining popularity, such as the Democratic Party for the People (DPFP) and Sanseito, a right-wing party that have been increasing their popularity by advocating a “Japan First” policy.

A Vigilant Path Ahead

The recent snap election has made Japan’s security direction clearer: the Takaichi administration will align with the realist strategies of the Trump administration, as reflected in the NDS, and will also actively accept greater burden-sharing.

With the opposition in the lower house now significantly weaker, Takaichi will likely promote bolder security policies more quickly than ever before, including the reform of Japan’s pacifist constitution, something even her mentor, Shinzo Abe, was unable to achieve.

While dissatisfaction with the Trump administration is growing across a number of countries, Trump will likely maintain a friendly stance toward Takaichi, who is fully supportive of his policies. However, since America First is the Trump administration’s unwavering top priority, the United States will continue to exert greater pressure on Japan.

Takaichi must constantly convince the Trump administration that cooperation with Japan is in the U.S. national interests. Despite the landslide victory in the election, the Takaichi administration’s security path will require constant vigilance.

Miki Hayashi is a PhD candidate in political science at UC Riverside and a 2025-26 IGCC Dissertation Fellow.

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