Japan’s Iran Dilemma: Oil, Alliances, and Nuclear Double Standards |
Tokyo Report | Diplomacy | East Asia
Japan’s Iran Dilemma: Oil, Alliances, and Nuclear Double Standards
For Japan, the crisis is not only about energy security. It also strikes at the heart of the country’s moral and strategic identity.
An F/A-18E Super Hornet, attached to Strike Fighter Squadron (VFA) 14, prepares to make an arrested landing on the flight deck of Nimitz-class aircraft carrier USS Abraham Lincoln (CVN 72) in support of Operation Epic Fury, the U.S. strikes on Iran, Mar. 1, 2026.
The large-scale Israeli-U.S. military strikes against Iran that began on February 28 – notably killing Supreme Leader Ayatollah Ali Khamenei – have sent shockwaves far beyond the Middle East. For Japan, the crisis is not only about energy security. It also strikes at the heart of the country’s moral and strategic identity.
Japan depends on the Middle East for more than 90 percent of its crude oil imports. Any escalation that threatens shipping through the Strait of Hormuz therefore poses a direct economic risk.
Even before the attacks, oil markets were on edge. On February 27, U.S. benchmark West Texas Intermediate (WTI) futures closed in the low $67 per barrel range, while Brent crude settled in the high $72 range – both roughly seven-month highs.
On March 2, oil surged the most in four years as the Middle East war all but halted shipping through the Strait of Hormuz. Brent crude jumped as high as about $82 per barrel and West Texas Intermediate approached $72 per barrel amid fears of prolonged supply disruption.
The immediate concern is not simply price volatility but the possibility of sustained disruption in Hormuz, the narrow waterway between Iran and Oman through which about one-fifth of global oil supply passes.
Following the strikes, Iran’s Islamic Revolutionary Guard Corps warned vessels against entering the strait. International media indicated that dozens of tankers altered course, while major Japanese shipping firms temporarily suspended passage. Although Japan maintains strategic reserves equivalent to roughly 240 days of consumption, a prolonged crisis would push up global prices and inevitably affect households and industry alike.
Against this backdrop, Tokyo has adopted a cautious diplomatic tone. Speaking before the Lower House Budget Committee on March 2, Prime Minister Takaichi Sanae stated that “Iran’s development of nuclear weapons can never be tolerated.” At the same time, she avoided explicitly endorsing or condemning the Israeli-U.S. operation, instead urging a diplomatic resolution. The calibrated ambiguity reflects Japan’s delicate position.
Japan is the United States closest treaty ally in Asia, yet it has historically maintained relatively cordial ties with Tehran. In 2019, then-Prime Minister Abe Shinzo visited Iran in an effort to mediate tensions between Washington and Tehran. Today, however, Tokyo’s room for maneuver is narrower. With a summit between Takaichi and U.S. President Donald Trump scheduled for March 19, alliance solidarity weighs heavily on the government’s calculations.
Yet the implications of the strikes extend beyond alliance management. They expose deeper contradictions in U.S. nuclear policy – contradictions that resonate acutely in Japan, the only country to have suffered atomic bombings in war, at Hiroshima and Nagasaki.
The United States is one of the five recognized nuclear-weapon states under the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). While the treaty legitimizes its possession of nuclear arms, it also obligates Washington under Article VI to pursue negotiations in good faith toward disarmament.
Nevertheless, the United States continues to modernize its arsenal, and progress toward global disarmament has stalled. Critics argue that condemning Iran’s nuclear ambitions – and now resorting to force – while failing to advance disarmament commitments fuels perceptions of selective enforcement, particularly in the Global South.
Meanwhile, Israel is widely believed to possess nuclear weapons but is not a party to the NPT and maintains a policy of strategic opacity. Successive U.S. administrations have refrained from directly challenging Israel’s undeclared arsenal, yet Iran’s alleged pursuit of nuclear weapons has led to intensive sanctions and, now, military strikes.
The contrast between Washington’s willingness to turn a blind eye to Israel’s nuclear program and the U.S. use of force against Iran reinforces accusations of double standards. A rules-based order depends on consistency; perceived exceptions weaken the normative foundations of the nonproliferation regime
For Japan, which advocates nuclear abolition yet relies on the U.S. nuclear umbrella, this contradiction is deeply uncomfortable. If the credibility of the NPT erodes, so too does a cornerstone of Japan’s postwar diplomacy.
The Trump administration’s approach to North Korea highlights yet another inconsistency in nonproliferation efforts. While maintaining formal opposition to Pyongyang’s nuclear program, Trump prioritized summit diplomacy with Kim Jong Un and at times downplayed the immediacy of North Korea’s arsenal.
The juxtaposition is striking: rhetorical accommodation of a de facto nuclear-armed North Korea alongside military action against Iran, which insists its program is civilian. Such contrasts risk sending the dangerous signal that possession of nuclear weapons deters intervention, while non-possession invites coercion. If that lesson takes hold internationally, the nonproliferation regime could be gravely weakened.
None of this absolves Tehran of responsibility for destabilizing activities in the region. But if the objective is to uphold a rules-based international order, selective enforcement carries long-term costs.
For Japan – a nation shaped by the atomic devastation of 1945 and situated within range of North Korean nuclear missiles – the stakes are profound. Tokyo depends on U.S. extended deterrence for its security, yet it also champions nuclear disarmament and the rule of law. The Iran strikes intensify the tension between alliance loyalty and normative consistency.
In an increasingly fragmented global order, perceptions of double standards can be as destabilizing as weapons themselves. Japan now faces a difficult diplomatic balancing act: safeguarding its alliance with Washington while upholding the universal principles that have defined its postwar identity.
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The large-scale Israeli-U.S. military strikes against Iran that began on February 28 – notably killing Supreme Leader Ayatollah Ali Khamenei – have sent shockwaves far beyond the Middle East. For Japan, the crisis is not only about energy security. It also strikes at the heart of the country’s moral and strategic identity.
Japan depends on the Middle East for more than 90 percent of its crude oil imports. Any escalation that threatens shipping through the Strait of Hormuz therefore poses a direct economic risk.
Even before the attacks, oil markets were on edge. On February 27, U.S. benchmark West Texas Intermediate (WTI) futures closed in the low $67 per barrel range, while Brent crude settled in the high $72 range – both roughly seven-month highs.
On March 2, oil surged the most in four years as the Middle East war all but halted shipping through the Strait of Hormuz. Brent crude jumped as high as about $82 per barrel and West Texas Intermediate approached $72 per barrel amid fears of prolonged supply disruption.
The immediate concern is not simply price volatility but the possibility of sustained disruption in Hormuz, the narrow waterway between Iran and Oman through which about one-fifth of global oil supply passes.
Following the strikes, Iran’s Islamic Revolutionary Guard Corps warned vessels against entering the strait. International media indicated that dozens of tankers altered course, while major Japanese shipping firms temporarily suspended passage. Although Japan maintains strategic reserves equivalent to roughly 240 days of consumption, a prolonged crisis would push up global prices and inevitably affect households and industry alike.
Against this backdrop, Tokyo has adopted a cautious diplomatic tone. Speaking before the Lower House Budget Committee on March 2, Prime Minister Takaichi Sanae stated that “Iran’s development of nuclear weapons can never be tolerated.” At the same time, she avoided explicitly endorsing or condemning the Israeli-U.S. operation, instead urging a diplomatic resolution. The calibrated ambiguity reflects Japan’s delicate position.
Japan is the United States closest treaty ally in Asia, yet it has historically maintained relatively cordial ties with Tehran. In 2019, then-Prime Minister Abe Shinzo visited Iran in an effort to mediate tensions between Washington and Tehran. Today, however, Tokyo’s room for maneuver is narrower. With a summit between Takaichi and U.S. President Donald Trump scheduled for March 19, alliance solidarity weighs heavily on the government’s calculations.
Yet the implications of the strikes extend beyond alliance management. They expose deeper contradictions in U.S. nuclear policy – contradictions that resonate acutely in Japan, the only country to have suffered atomic bombings in war, at Hiroshima and Nagasaki.
The United States is one of the five recognized nuclear-weapon states under the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). While the treaty legitimizes its possession of nuclear arms, it also obligates Washington under Article VI to pursue negotiations in good faith toward disarmament.
Nevertheless, the United States continues to modernize its arsenal, and progress toward global disarmament has stalled. Critics argue that condemning Iran’s nuclear ambitions – and now resorting to force – while failing to advance disarmament commitments fuels perceptions of selective enforcement, particularly in the Global South.
Meanwhile, Israel is widely believed to possess nuclear weapons but is not a party to the NPT and maintains a policy of strategic opacity. Successive U.S. administrations have refrained from directly challenging Israel’s undeclared arsenal, yet Iran’s alleged pursuit of nuclear weapons has led to intensive sanctions and, now, military strikes.
The contrast between Washington’s willingness to turn a blind eye to Israel’s nuclear program and the U.S. use of force against Iran reinforces accusations of double standards. A rules-based order depends on consistency; perceived exceptions weaken the normative foundations of the nonproliferation regime
For Japan, which advocates nuclear abolition yet relies on the U.S. nuclear umbrella, this contradiction is deeply uncomfortable. If the credibility of the NPT erodes, so too does a cornerstone of Japan’s postwar diplomacy.
The Trump administration’s approach to North Korea highlights yet another inconsistency in nonproliferation efforts. While maintaining formal opposition to Pyongyang’s nuclear program, Trump prioritized summit diplomacy with Kim Jong Un and at times downplayed the immediacy of North Korea’s arsenal.
The juxtaposition is striking: rhetorical accommodation of a de facto nuclear-armed North Korea alongside military action against Iran, which insists its program is civilian. Such contrasts risk sending the dangerous signal that possession of nuclear weapons deters intervention, while non-possession invites coercion. If that lesson takes hold internationally, the nonproliferation regime could be gravely weakened.
None of this absolves Tehran of responsibility for destabilizing activities in the region. But if the objective is to uphold a rules-based international order, selective enforcement carries long-term costs.
For Japan – a nation shaped by the atomic devastation of 1945 and situated within range of North Korean nuclear missiles – the stakes are profound. Tokyo depends on U.S. extended deterrence for its security, yet it also champions nuclear disarmament and the rule of law. The Iran strikes intensify the tension between alliance loyalty and normative consistency.
In an increasingly fragmented global order, perceptions of double standards can be as destabilizing as weapons themselves. Japan now faces a difficult diplomatic balancing act: safeguarding its alliance with Washington while upholding the universal principles that have defined its postwar identity.
Takahashi Kosuke is Tokyo Correspondent for The Diplomat.
Israel-U.S. strikes on Iran