Japan’s Prime Minister, Sanae Takaichi, has already made history since taking office in October 2025. Capitalising on her high approval ratings and “fresh new image”, she dissolved the lower house and called an election just four months into her term.
Her gamble paid off, winning the Liberal Democratic Party (LDP) more seats in the lower house than any party in post-war Japan: 316 of a possible 465. Its coalition partner, the Japan Innovation Party (JIP), won a further 36 seats.
With a strong (and resoundingly consolidated) mandate, Takaichi is now making moves to revise Japan’s Constitution, and effectively revoke the pacifist Article Nine that has defined the country’s identity as a peaceful nation since the end of World War II.
Post-pacifist Japan
Article Nine of Japan’s post-war Constitution is one of its most controversial provisions, but it has also played a key role in shaping the country’s national identity. It states that Japan renounces “war as a sovereign right of the nation” and “the threat or use of force as a means of settling international disputes”. The second part adds that to achieve this aim, “land, sea, and air forces, as well as other war potential, will never be maintained.”
Article Nine has been interpreted to mean that Japan cannot maintain a traditional military, allowing only the Self-Defense Forces (SDF). Although the SDF is one of the most capable militaries in the world, its functions are limited by strict constitutional restrictions. Even so, many in Japan still consider the very existence of the SDF to be “war potential” and therefore unconstitutional.
The LDP has long advocated revising Article Nine to formally incorporate the SDF into the Constitution. Another major demand is to move beyond Japan’s exclusive self-defense posture to allow for collective self-defense. This would enable Japan to aid allies such as the United States even when Japan itself is not directly threatened.
Any constitutional revision would require a two-thirds majority in both houses of Japan’s National parliament (known as the Diet) followed by a national referendum. This makes the task extremely challenging – no such revision has ever been achieved in Japanese politics to date.
Barriers to revising the Constitution
At a press conference held after securing the supermajority in February 2026, Takaichi reaffirmed her commitment to constitutional revision, saying that she will carry out a national referendum for constitutional revision “as soon as possible”.
While the lower house majority gives her a strong starting point, the LDP still lacks a two-thirds majority in the upper house. With the support of the JIP and a few other pro-revision or independent members, she might reach the necessary threshold. Without them, she would have to wait for the upper house election in 2028.
However, political popularity in Japan can be fickle, and the LDP’s performance in the next election is certainly not guaranteed. The country is often described as having “revolving door” leadership, with 13 prime ministers between 1993 and 2026. Germany, for comparison, had only three Chancellors during the same period.
Even with the strongest of mandates, Japanese leadership is still heavily influenced by approval ratings and other structural factors, all of which contribute to a high degree of political instability.
A national referendum will present further hurdles. Despite the lower house supermajority, the LDP’s total vote share was only 37%. Winning a national referendum would require over 50% support.
As an alternative, Takaichi may follow her predecessors’ path, gradually chipping away at Article Nine through legislation or reinterpretation. This would avoid some of the procedural hurdles of formal amendment.
Read more:
Make Japan strong again: Sanae Takaichi’s plan to transform her country’s military
What would constitutional revision mean for Japan?
The impact would depend on the specific changes introduced. Abe sought to formally include the SDF in Article Nine, which Takaichi may also pursue. The JIP, however, advocates completely deleting the second part of Article Nine. Either way, any official revision would move Japan away from its pacifist principles.
Some fear this could mean Japan is “militarising”, but this term is misleading. The revision would instead make Japan a normal country in terms of international rights and responsibilities under the UN charter. Nuclear weapons remain highly unlikely, but Japan would play a greater role in regional security and international peacekeeping.
Neighbouring countries such as China, South Korea and North Korea are likely to view such a revision with suspicion, while the United States would welcome Japan taking on more responsibility for its national and regional security. For Takaichi herself, successfully revising the Constitution would likely be the crowning achievement of her political career.
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