Japan: Caught Between the Houthis and Hormuz

Today, I would like to introduce , a former diplomat, senior political analyst, Middle East specialist, and CEO of Red Sea Futures. He has held fellowships and research positions at various prestigious institutions, and he is the author of several books, including Benghazi!: A New History of the Fiasco that Pushed America and its World to the Brink (Hachette, 2022).

His analysis is characterized by his commitment to providing detailed and balanced accounts of events in the Middle East. This approach is rooted in his long-standing collaborations with people in the region, his profound understanding of diplomacy, and his extensive knowledge of world and regional history. His work is also characterized by a profound sense of humanity, a quality often absent from today’s policies, analyses, and discussions.

In response to Iranian mining of the Strait of Hormuz and broader threats to oil shipping through the Persian Gulf, President Trump recently called on Japan — along with France, South Korea, the UK, and even China — to contribute to the defense of shipping through the straits. This despite serious questions about whether such support would even be effective. Japan’s newly elected Prime Minister Sanae Takaichi has said no, citing high legal barriers, even as she is set to meet Trump on March 19 to affirm support for US-Japan ties. Those legal barriers center on Article 9 of the Japanese constitution, which was drafted under American occupation and came into effect in 1947. Few situations have tested the practical limits of Article 9 more concretely than the question of Japan’s role in protecting shipping through the lower straits of the Red Sea and Persian Gulf.

Article 9 — Renunciation of War

Japan’s dilemma with respect to responding to President Trump’s urgings in the current “Iran war” is not trivial. Article 9 was meant to foreclose Japan’s participation in any large-scale hostility of the kind it had prosecuted across Asia and the Pacific during World War II. The constitution was drafted quickly with input from General MacArthur’s staff in 1946 (recent scholarship crediting Japanese Prime Minister Shidehara as the originator of the pacifist clause), reflecting American strategic intent and genuine exhaustion among ordinary Japanese with the militarist establishment that had led the country to catastrophic defeat.

Over the decades, the article’s ambiguous language was interpreted and re-interpreted in ways that gradually expanded Japan’s military options, without a formal constitutional amendment. Every expansion of its military role has come through reinterpretation and enabling legislation, a legally precarious but politically convenient approach. A key innovation was the creation of the Self-Defense Forces, making self defense from existential harm explicitly legitimate. This was not unexpected, but it was also, tellingly, partly in response to American pressure to have a forward base in Japan to deal with the Korean War. In 2009, Japan contributed maritime patrol vessels to counter-piracy operations in the Gulf of Aden; and in 2015, under Prime Minister Abe, the government passed landmark legislation reinterpreting the constitution to allow for three categories of military action — individual self-defense, collective self-defense to assist allies facing threats to mutual security, and Maritime Security Operations (MSOs) in lower-risk environments.

It is worth noting that Takaichi is one of the most defense-forward prime ministers Japan has had in recent years — a protégée of Shinzo Abe, and a long-standing advocate for revising Article 9 outright. Takaichi holds a two-thirds supermajority in the lower house, which is the procedural minimum to initiate a constitutional amendment. That she is the one invoking the legal barrier suggests either a genuine domestic political constraint, or a negotiating position ahead of her meeting with Trump on the 19th — likely both.

The Houthi Case

The question of the meaning and implementation of Article 9 in the current conflict follows a series of challenges in recent years within the lower Red Sea, following the outbreak of Red Sea piracy in the early 2000s. Japan’s National Diet passed enabling anti-piracy legislation in 2009, and Japan sent two JMSDF destroyers.

A formal base — the first outside of Japan since WWII — was opened in the small Red Sea state of Djibouti — directly adjacent the Bab Al Mandeb — in 2011 at a cost of roughly $40 million, hosting 180 troops on a rotating basis. The base has since expanded — partly to support evacuation of Japanese nationals from unstable neighbors, and partly as a strategic counterweight to China, which opened its own first overseas military base in Djibouti in 2017. Japan’s base sits directly opposite the shores from which the Houthis were attacking international shipping. And yet when the threat escalated from Somali pirates — unambiguous non-state actors — to Houthi forces with Iranian backing, quasi-state organization, and ballistic missiles, Japan’s forces stayed put. Indeed, in 2024, Japan preferred to direct vessels the long way around the Cape, absorbing the associated cost, rather than provide an escort.

The official rationale for non-engagement was that the moment Japan placed armed forces into a zone of potential combat, any exchange of fire would be a proscribed act of war, unjustified by any claim of existential threat to the homeland. The Houthis’ quasi-state characteristics — controlling significant territory, fielding sophisticated weapons, backed by a sovereign state in Iran — made the offense even more serious than it would have been against the Somali pirates.

The Sasakawa Peace Foundation, one of Japan’s leading security think tanks, was withering in its assessment of this reasoning. Given the scale and indiscriminate nature of Houthi attacks — hundreds of incidents, Japanese-operated vessels seized, crews taken hostage — the foundation argued that Japan’s legal formula declaring no “immediate need” for vessel protection had become factually indefensible. Japan was choosing not to acknowledge a threshold that had plainly been crossed. The constitutional argument, the foundation suggested, had become a political argument wearing legal clothes.

China, Japan, and the Illusion of Shared Vulnerability

There has been considerable discussion about Asia’s disproportionate vulnerability to Persian Gulf oil supplies — but China and Japan’s positions are substantively different, and the distinction matters. China has built genuine alternatives over decades: overland pipelines from Russia and Central Asia, equity oil investments across Africa and Latin America, and the geopolitical flexibility to buy from sanctioned states that Japan, under American alliance pressure, cannot. Japan is an island with no pipeline access to anything, allied to a power that constrains its supplier options, and dependent on maritime routes it cannot independently defend. While Japan maintains stockpiles capable of absorbing short-term disruption, a prolonged conflict could put it under extreme and compounding pressure — caught simultaneously between geographic vulnerability and political constraint in a way that China, for all its own dependencies, simply is not.

The Hormuz Case

In the case of the current war with Iran, the contradictions with Article 9 are both more and less severe — for roughly 90% of Japan’s oil imports transit the Persian Gulf. Unlike the Red Sea, where rerouting around Africa was costly but viable, there is no meaningful alternative to Hormuz. This arguably could be framed as an existential threat to the Japanese homeland; at the same time, Iran is unambiguously a sovereign nation, now in open conflict with the United States and Israel.

Once again, as with the Houthis in 2024, Japan can choose to absorb the economic cost for the time being — and will presumably need to do so regardless, at least initially. If it were to join efforts to clear the straits, this would put Japan directly, as an actor, into an international conflict of contested legal sanction and uncertain military outcome. Japan’s ruling party policy chief captured the bind precisely when he told NHK this week that “the legal threshold is very high,” adding that while Japan does “not rule out the possibility,” it must proceed “with great caution.”

There is, however, a precedent for a narrower form of participation that could thread this needle. Following the 1991 Gulf War, Japan sent minesweepers to the Persian Gulf for post-conflict demining operations — after the ceasefire, not during hostilities. This allowed Japan to contribute meaningfully to regional security, demonstrate alliance solidarity, and avoid the belligerency problem entirely. It is the one available model that fits within Article 9’s constraints as currently interpreted, and it may be what Tokyo is quietly banking on as a face-saving off-ramp — assuming the conflict reaches a ceasefire before the economic pressure becomes unbearable.

Full Circle

Article 9 has been called the most concrete implementation of a spirit of democratic anti-militarism following WWII — a genuine attempt to constitutionalize the lessons of catastrophic war. Yet it has been continuously forced, by other powers and allies, to shape and retreat from its absolutism.

There is also a more fundamental question that the legal debate tends to obscure: whether a military escort would offer meaningful protection in the first place. The current threat environment in the strait — mines, drone boats, anti-ship missiles, and the possibility of Iranian midget submarines — is categorically different from the piracy scenarios that shaped Japan’s existing legal frameworks. Analysts have estimated that even a robust escort force of seven or eight destroyers could protect no more than three or four commercial vessels per day. More telling still, the shipping industry itself has answered the question of acceptable risk in its own terms. Maersk CEO Vincent Clerc, speaking to CNN and the Wall Street Journal, was unambiguous: with ten ships already trapped in the Upper Gulf and unable to exit, Maersk suspended all Hormuz transits indefinitely. “The safety of our crews, vessels and customers’ cargo remains our key priority,” the company stated. Clerc described the situation as “uncharted territory,” adding that even if a ceasefire were reached it would take a week to ten days to resume normal operations. The implicit judgment is clear — no military escort on offer is likely to change that calculus. Japan is therefore being asked to cross a constitutional threshold, and risk a rupture in its most important alliance, to protect ships that the shipping industry itself has already decided not to send.

The political pressure continues regardless. President Trump, by suggesting that Japan — and others — are freeloading, is attempting to bring them over to a view of international realism that is the very opposite of Japan’s starting point in Article 9 — and to assist in a war that lacks sanction under international law. And yet by refusing, Japan opens itself up to alliance strain, trade pressure, and the growing domestic cost of oil supply disruption. It is a dilemma with no clean exit.

The Middle East-Told Slant

Former US diplomat, exploring themes in American Middle East policy. Author of "Benghazi: A New History", Exit The Colonel, and forthcoming history of the Red Sea. Past contributor to Foreign Affairs, NYT, FT, FA, etc.

By Ethan D. Chorin