argued in\u00a0Foreign Affairs\u00a0this summer<\/a> that the traditional U.S. nuclear umbrella is coming under increasing strain as adversaries acquire more credible means of striking the U.S. homeland. Their argument revives a long-standing concern about \u201cdecoupling\u201d: whether Washington would risk devastating retaliation against the United States in order to defend an ally such as Japan or South Korea.<\/p>\nPut more starkly, the question is this: Would an American president risk Los Angeles to defend Tokyo or Seoul?<\/p>\n
Under an \u201cAmerica First\u201d posture in Washington, that question carries added political weight. The credibility of extended deterrence ultimately depends on whether an adversary believes Washington would accept the risk of nuclear retaliation to defend an ally.<\/p>\n
Inside Japan, meanwhile, the reluctance to discuss nuclear deterrence openly is gradually eroding. Defense Minister Koizumi Shinjiro has argued that nuclear issues can no longer simply be avoided in policy discussions. Former Joint Staff Chief Kawano Katsutoshi has similarly questioned whether Japan can indefinitely assume that the American nuclear umbrella will hold, calling for a broader national debate.<\/p>\n
Takaichi herself raised the underlying issue well before becoming prime minister. In a 2024 book, she revealed that, as a Cabinet minister in 2022, she had objected to language in the National Security Strategy stating that Japan\u2019s basic policy of adhering to the Three Non-Nuclear Principles would remain unchanged.<\/p>\n
Takaichi argued that if Japan expected U.S. extended deterrence to remain credible, the third principle \u2013 \u201cnot permitting the introduction\u201d of nuclear weapons \u2013 was unrealistic. She wrote that she ultimately signed off on the Cabinet decision reluctantly after her request to remove the language was rejected.<\/p>\n
That history gives greater significance to her carefully chosen wording in Hiroshima and Nagasaki this year.<\/p>\n
The tension could become more concrete in the early 2030s. The U.S. Navy is developing a nuclear-armed Sea-Launched Cruise Missile, or SLCM-N, for integration aboard Virginia-class attack submarines. Tokyo will eventually have to ask whether strict adherence to \u201cnot permitting the introduction\u201d is compatible with port visits by U.S. platforms potentially carrying such weapons, particularly if Washington maintains its traditional policy of neither confirming nor denying their presence.<\/p>\n
The dilemma already impacts Japan\u2019s defense diplomacy. For example, France\u2019s nuclear-powered aircraft carrier,\u00a0the Charles de Gaulle,\u00a0has never called at a Japanese port. During Operation Clemenceau 25, its 2024-2025 Indo-Pacific deployment, the carrier visited Indonesia, the Philippines, and Singapore \u2013 but not Japan.\u00a0<\/p>\n
Its embarked Rafale M fighters are capable of carrying France\u2019s nuclear-armed ASMP-A air-launched cruise missile, although Paris does not publicly confirm or deny whether nuclear weapons are present aboard its strategic platforms.<\/p>\n
Rear Admiral Guillaume Pinget, then-commander of the French Pacific Command, told this author in a July interview that France respects Japan\u2019s laws and regulations and does not regard them as limiting the bilateral defense partnership. But he stopped short of predicting whether\u00a0the Charles de Gaulle\u00a0would eventually visit Japan.<\/p>\n
\u201cIf Japan invites France to come, we will see,\u201d Pinget said.<\/p>\n
The case illustrates the potential friction between Japan\u2019s non-nuclear policy and the nuclear deterrence postures of its partners.<\/p>\n
Abandoning the Three Non-Nuclear Principles hastily would carry substantial political and diplomatic costs. They remain closely tied to Hiroshima and Nagasaki and underpin Japan\u2019s credibility in advocating global nuclear disarmament.<\/p>\n
But treating the principles as untouchable regardless of strategic change carries risks of its own, including a widening gap between declared policy and the deterrence architecture Japan\u2019s allies are building around it.<\/p>\n
For Japan, the choice is not simply whether to pursue nuclear armament or nuclear pacifism. The more immediate question is whether the third principle specifically \u2013 \u201cnot permitting the introduction\u201d of nuclear weapons \u2013 can remain unchanged while Japan simultaneously asks the United States to strengthen extended nuclear deterrence.<\/p>\n
The year-end revision of Japan\u2019s security documents offers an opportunity to address that contradiction openly. Takaichi\u2019s government must explain whether changing the third principle would materially strengthen deterrence \u2013 and whether any security benefits would outweigh the political and diplomatic costs.<\/p>\n
Eighty-one years after Hiroshima and Nagasaki, avoiding that question is itself becoming a strategic choice.<\/p>\n","protected":false},"excerpt":{"rendered":"Eighty-one years after the atomic bombings of Hiroshima on August 6, 1945, and Nagasaki on August 9, Japan…\n","protected":false},"author":2,"featured_media":72974,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[374,8,46933,33,5892,41025,3427,46934,46935],"class_list":["post-72973","post","type-post","status-publish","format-standard","has-post-thumbnail","category-japan","tag-east-asia","tag-japan","tag-japan-nuclear-allergy","tag-nihon","tag-security","tag-takaichi-security-policy","tag-three-non-nuclear-principles","tag-u-s-extended-deterrence","tag-u-s-nuclear-weapons-in-japan"],"_links":{"self":[{"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/posts\/72973","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/comments?post=72973"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/posts\/72973\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/media\/72974"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/media?parent=72973"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/categories?post=72973"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/tags?post=72973"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}