The Mogami Memorandum & the New Frontier for Japanese Arms Sales
Japan’s frigate deal with Australia marks a major step away from its postwar restraints on arms exports.
On Saturday, April 18th, officials from the Japanese and Australian defense ministries gathered in Melbourne to sign Japan’s most extensive arms deal since repealing part of its longstanding weapons export ban in 2014. The formal ceremony cemented a $7 billion warship package to provide Canberra with critical upgrades to its navy in the face of expanding Chinese maritime influence. For Tokyo, it legitimizes a burgeoning defense manufacturing industry to a rapidly expanding global market, and marks yet another step in Japan’s decades-long journey away from constitutional pacifism.
Although terms had been unofficially agreed upon last August, the public unveiling of the “Mogami Memorandum” still impressed with the enormity of its transactional provisions. Under contract with Mitsubishi Heavy Industries, Japan will build three Mogami-class stealth frigates by 2029, with eight more to be built in Australia by Austal. International bidding for the contract had been intense, with Mitsubishi ultimately winning out in the naval manufacturing sweepstakes.
“Our surface fleet is more important than at any time in decades,” Australian Defense Minister Richard Marles said in a statement following the signing. “These general-purpose frigates will help secure our maritime trade routes and northern approaches as part of a larger and more lethal surface combatant fleet.”
When considered within the lens of Japan’s historic and institutional hostility towards arms exports, the deal becomes even more impressive. The near-total 1967 weapons export ban functioned for half a century as a pillar of Tokyo’s foreign policy, and despite the relaxation of certain restrictions in 2014, it still wielded enormous influence in Japanese governance. Originally, under heavy U.S pressure during the Cold War, the ban was designed to prevent any future arms agreement with the communist bloc, and later extended to include any nation under sanction by the United Nations. And while the updated terms in 2014, known as the “Three Principles on Transfer of Defense Equipment and Technology, still kept much of the historic restrictions intact, it signaled a new, far more profitable era for domestic defense manufacturers.
Since jumpstarting its fragile defense industry in 2014, companies like Mitsubishi have seen steady growth despite stiff competition from far more storied, global competitors. Shortly after the new guidelines were established, Japan began selling missile interceptor components to the United States, which was soon followed by increased attention from militaries in the market for defense upgrades. In 2015, India requested that Japanese defense companies enter the bid for the Project-India-75 program, originally intended to build six diesel-electric submarines. Later that year, rumors circulated that Australia was interested in purchasing Soryu-class submarines, although the deal never materialized. Four years later, Japan sold its first major weapons package to the Philippines, supplying air-surveillance radars to Rodrigo Duterte’s government.
Powered by companies like Mitsubishi, Kawasaki Heavy Industries, NEC, and Fujitsu, the statistical evidence for growth in Japan’s defense industry was clear even before the Mogami Memorandum. According to the Stockholm International Peace Research Institute (SIPRI), in 2024 alone, sales from these top weapon manufacturers rose by 40%, totalling $13.3 billion. given the symbolic nature of Australia’s decision to trust the Japanese defense industry with naval upgrades, that number is expected to continue to rise in the coming years.
There are already rumors that several regional powers are considering following Australia’s lead. Indonesia has also expressed interest in purchasing Mogami-class warships, including a discussion on the prospect of a joint development program. Perhaps the biggest potential suitor is the Philippines, which was already showing interest in acquiring some of Japan’s TC-90 aircraft. This, alongside recent talks regarding the purchase of the Chu-SAM Medium-Range Surface-to-Air Missile system, and discussions regarding a deal to obtain several Abukuma-class destroyers, signals that a series of lucrative deals between Manila and Tokyo may be the next big line item for Japan’s defense industry.
Additionally, the possibility for further investment and cooperation in Australia looms large, where Prime Minister Anthony Albanese recently announced that defense spending is set to rise to 3% of total GDP, constituting the largest increase in defense spending for the island nation since World War 2. It’s an opportunity that the fledgling Japanese defense industry is keenly aware of, and one that Japan’s new nationalist Prime Minister Sanae Takaichi has wasted no time in encouraging. Barely a day after the naval deal was signed, Takaichi’s cabinet approved a comprehensive authorization of lethal weapons sales, completely axing what was left of the 2014 ban.
Despite this seemingly new frontier for domestic weapons exports, the Japanese government continues to maintain, at least publicly, its historic self-defense first doctrine. “No country today can defend peace and safety by itself and needs partners to support each other,” Prime Minister Takaichi posted to X, shortly after the abolition of the lethal weapons ban, adding, “There is no change to our 80-year history as a pacifist nation and its pledge.”
Despite fervent protest from Tokyo, the Mogami Memorandum demonstrates that a new age of Japanese arms sales has arrived. Coupled with the rumors of impending naval packages for expanding markets in the Philippines, and the Takeuchi Government’s decision to drastically reduce weapon sales regulations, it’s clear that Japan intends to utilize its adolescent defense industry for diplomatic and strategic purposes. In the long term, this may mirror the U.S. arms industry, creating weapons dependencies in developing powers that can be leveraged for influence. However, in the short term, it is almost certainly a response to growing Chinese aggression in the South China Sea and a noteworthy escalation in Japan’s gradual abolition of its postwar commitment to pacifism.
The views and information contained in this article are the author’s own and do not necessarily represent those of The Asia Cable.