Asia Defense

Japan Dispatches Biggest Warship to Protect US Navy Vessel, Putting New Security Law to Work

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Asia Defense

Japan Dispatches Biggest Warship to Protect US Navy Vessel, Putting New Security Law to Work

Japan has issued its first order to protect a U.S. Navy warship under the country’s new security legislation.

Japan Dispatches Biggest Warship to Protect US Navy Vessel, Putting New Security Law to Work
Credit: Wikimedia Commons/Kaijō Jieitai

Japan’s Ministry of Defense (MoD) dispatched the helicopter carrier JS Izumo, the lead ship of the Izumo-class, to protect a U.S. Navy supply ship in the Pacific on May 1, according to Japanese government sources.

It is the first time that Japan has issued an order to the Japan Maritime Self Defense Force (JMSDF) to protect assets of an ally since new security legislation — the so-called Permanent International Peace Support Law and the Legislation for Peace and Security — was enacted by the Upper House of the Japanese Diet in 2015 and came into force in March 2016.

Based off the revised U.S.-Japan defense cooperation guidelines, the new security legislation allows the Japan Self Defense Force to protect U.S. forces, including American warships, in peacetime. The use of force to protect allied assets such as U.S. ships and aircraft is permissible under the new security law if certain criteria are met, as outlined below:

  • The operation is carried out outside an ongoing combat zone;
  • the U.S. assets to be protected are contributing to the defense of Japan;
  • the U.S. government specifically requested the Japanese military to protect its vessels or aircraft;
  • the Japanese Defense Minister has authorized the operation (there is no need for a Diet approval).

Following the order given by Japanese Defense Minister Tomomi Inada in late April, the JS Izumo escorted a U.S. Navy supply ship off the coast of the the Boso Peninsula, in Chiba Prefecture, to the area off Shikoku, one of the four main islands of Japan, according to the Nikkei Asian Review.

The Japanese MoD did not reveal additional details about the JS Izumo’s mission and it is unclear whether the warship has been escorting other American vessels while deployed. The U.S. Navy supply ship resupplied other American warships currently cruising off the Korean Peninsula.

JS Izumo, along with its recently commissioned sister ship JS Kaga, is the biggest surface warship operated by the Japanese Navy since the end of the Second World War. As I noted elsewhere, “the JMSDF officially classified the warships’ as helicopter destroyers in order to downplay the carriers’ offensive capabilities.”

The carrier is a multipurpose warship and can be deployed for surveillance and humanitarian assistance and disaster relief missions, as well as anti-submarine warfare operations.

“The ship is designed to accommodate up to 14 helicopters (seven Mitsubishi-built SH-60k ASW helicopters and seven Agusta Westland MCM-101 mine countermeasure helicopters), five of which can simultaneously take off and land, given the Izumo’s large flight deck and five landing spots,” I explained previously.

The JS Izumo is part of the JMSDF’s Escort Flotilla 1 based in Yokosuka, Kanagawa Prefecture, which is also home to the U.S. Navy’s only forward deployed aircraft carrier USS Ronald  Reagan.