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Four legal frameworks related to Japan’s participation in coalition to ensure security in waters off Iran

  • July 12, 2019
  • , Sankei , p. 2
  • JMH Translation

By Kei Ishinabe


The United States aims to form a coalition of the willing with its allies to escort commercial vessels passing through the Strait of Hormuz off the coast of Iran and neighboring areas. The Japanese government plans to carefully look into what Japan can do. In preparation for the event that it receives an official request to dispatch the Self-Defense Forces (SDF), Japan has initiated work behind the scenes to determine actions the SDF can take, but issues remain in dispatching the SDF.


At a press conference on July 11, Koji Yamazaki, chief of the SDF’s Joint Staff, touched on Japan’s response regarding the coalition, saying, “It is true that Japan and the United States are communicating over a range of matters. I will refrain from going into the details.”


If the SDF were to participate in the coalition, four legal frameworks would come into play.


Maritime patrol operations based on the Self-Defense Forces Act can be ordered by the Minister of Defense with the approval of the Prime Minister in the case that there is deemed to be a need to protect lives or assets at sea.


In principle, the patrol operations must be for ships related to Japan, and patrol is possible even if none of the crew members are Japanese if the vessel’s destination is Japan. The use of weapons is limited to the minimum necessary, such as for legitimate self-defense and emergency evacuation. Such an order has been issued three times in the past, including in the case of suspicious vessels in waters off the Noto Peninsula in 1999.


If the counterpart is confirmed to be a pirate, the SDF can provide escorting based on the Anti-Piracy Measures Law. The SDF can take such responses as firing at pirates who are inflicting harm on commercial vessels. Since 2009, the Maritime Self-Defense Force has engaged in anti-piracy activities in the Gulf of Aden off the coast of Somalia. One SDF escort ship and two P3C patrol planes are currently being dispatched.


There is also a framework under the security legislation, which was enacted in 2015. In situations deemed to have an “important influence” on Japan’s peace and security where there is a risk of an armed attack on Japan, the SDF can provide U.S. and multinational forces with logical support, including supply and transport activities. To make that assessment, however, requires a high-level political decision.


Under the new law, the SDF can exercise collective self-defense if the situation falls under the category of “situations that constitute a threat to Japan’s survival,” but the hurdles are even higher. The conditions for the exercise of collective self-defense include situations that constitute a “threat to Japan’s survival and pose a clear danger to fundamentally overturn people’s right to life, liberty and the pursuit of happiness.”


There is also the option of enacting new legislation as a special measures law with a set period of validity. It would take considerable time, however, to deliberate and enact such legislation in the Diet, so it would be difficult to respond to the U.S. request, which seeks a prompt response.


Legal framework in Japan


Security legislation 

  • Logistical support in situations that have an “important influence” on Japan’s peace and security
  • Exercise of right to collective self-defense in “situations that constitute a threat to Japan’s survival”

Strict conditions must be fulfilled so it will be hard to dispatch SDF

Maritime patrol operations

  • Guarding of vessels related to Japan based on the Self-Defense Forces Act

Foreign ships are not covered

Anti-Piracy Measures Law

  • Responses to piracy, including firing at pirates

Not applicable in cases other than piracy

Enactment of special measures law

  • Enactment of new legislation to participate in the coalition

It will take time to draft the legislation and deliberate it in the Diet


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