Article 9 of Japan's 1947 Constitution represents the postwar pledge Japan made to the world. Born from deep reflection on the country's wartime aggression, the landmark peace clause declares that Japan "forever renounces war as a sovereign right of the nation." It also prohibits "the maintenance of land, sea, and air forces, as well as other war potential."

Nearly eight decades later, however, Japan's military reality presents a starkly different picture. The country's defense budget has risen for 14 consecutive years, while its arms imports increased by 76 percent over the past five years. Japan has also eased restrictions on arms exports, including lethal weapons, and deployed long-range missiles, among other steps aimed at accelerating its military buildup.

According to Zhang Yun, a professor at Nanjing University's School of International Studies, although the wording of Article 9 has remained unchanged for decades, its underlying pacifist principles have been gradually eroded.

Japan's Liberal Democratic Party (LDP) has sought to revise the Constitution since its founding in 1955. However, constitutional amendment is a difficult process, requiring a two-thirds majority in both houses of the Diet before the proposal can be put to a national referendum. Faced with these procedural hurdles, Japan's right-wing forces have instead pursued an alternative approach: reinterpreting the Constitution and enacting new laws to work around the restrictions imposed by Article 9, Zhang says.

This is how the hollowing-out has worked: the text stays the same, while the meaning of what it permits is gradually expanded.

To see how far that meaning has shifted, we first need to look at Japan's "exclusively defense-oriented policy." Shaped by Article 9, it is, in the words of Japan's Ministry of Defense, the basic policy for the defense of Japan, one that permits the use of defensive force only when Japan comes under attack, keeps that force to the minimum necessary for self-defense, and limits the defense capabilities Japan possesses to the same minimum.

In July 2014, Prime Minister Shinzo Abe's cabinet reinterpreted Japan's Constitution to allow the exercise of collective self-defense. Abe described the move as a matter of "finding the appropriate interpretation." In practice, it expanded the role of the Self-Defense Forces from defending Japan alone to also defending a "foreign country in a close relationship with Japan."

The following year, in September, after more than 200 hours of deliberation, Japan's Diet passed legislation for the first time allowing the exercise of the right to collective self-defense. The bills met fierce opposition. Members of the Japan Federation of Bar Associations rallied in Tokyo alongside academics and citizens' groups. Its chairman, Susumu Murakoshi, warned that if the bills were passed, the Constitution "couldn't work as a constitution."

According to Zhang Yun, Kishida's cabinet took this approach a step further. In December 2022, the cabinet approved three updated documents outlining Japan's security and defense policies, including the new National Security Strategy (NSS). The new NSS called for Japan to acquire "counterstrike capability," effectively broadening the scope of what could be considered the "minimum necessary" level of defense under the country's exclusively defense-oriented policy.

These documents soon translated into a concrete military buildup: sharply increasing defense spending, purchasing and deploying large quantities of US missiles and easing long-standing restrictions on arms exports.

Atsushi Koketsu, former vice president of Yamaguchi University, warned that the three documents represent a fundamental shift in Japan's defense policy, abandoning the principle of "exclusively defense" in favor of what he described as a "preemptive attack strategy."

Now, under Prime Minister Sanae Takaichi, the focus is moving from constitutional reinterpretation toward formal constitutional revision. At a party convention, she stressed that "the time has come" to reform the Constitution and expressed hope that next year's convention would be held with a proposed amendment already in sight.

From Abe to Kishida and now Takaichi, Japan has employed a "salami-slicing" strategy to gradually erode its postwar pacifist framework, paving the way for further military expansion.

Japan has repeatedly invoked so-called "security threats in its neighborhood" to justify its military buildup. But when a country refuses to confront its wartime past, who, in the end, is the real threat?