Amid heightened tensions with North Korea, the Japanese government on May 1 ordered the Maritime Self-Defense Force (MSDF) helicopter carrier Izumo to escort a U.S. Navy supply ship from off the coast of Chiba Prefecture's Boso Peninsula south to waters near Shikoku. It is the first allied vessel escort mission undertaken by the MSDF under security legislation that came into force in 2016.
Though North Korea is not seen as a threat to shipping on the Pacific Ocean side of Japan, the Izumo's deployment "is extremely significant as a demonstration of the strength of the Japan-U.S. alliance's deterrent power and responsiveness," Foreign Minister Fumio Kishida was quoted as saying by Kyodo News on May 1 during an official visit to Turkmenistan.
The USS Carl Vinson carrier strike group is currently conducting joint maneuvers with the South Korean Navy in waters off the Korean Peninsula. The ship being accompanied by the Izumo is likely sailing for the same area to resupply U.S. Pacific Fleet warships, including the carrier group, monitoring North Korean activity.
The United States formally requested the Japanese government to provide an escort for the U.S. Navy supply ship. While the Japanese government has made no announcement, it appears that Defense Minister Tomomi Inada's deployment order was approved at an April 29 National Security Council (NSC) meeting following North Korea's latest missile test attempt.
The move appears intended as a political message to Pyongyang that Japan and the U.S. stand united in increasing the military pressure on North Korea, as the regime of Kim Jong Un continues its provocations in the face of both the growing U.S. military presence in the region and Chinese-led international calls for restraint.
The Izumo, commissioned in March 2015, is the MSDF's largest helicopter carrier. With a flat flight deck extending from bow to stern, the Izumo resembles an aircraft carrier. Up to five helicopters can land on or take off from the flight deck at a time, and there is space for nine more on the hangar deck, making the Izumo ideal for reconnaissance missions including tracking submarines.
However, the Izumo is not sufficiently armed to guard other vessels. Designed to help defend Japan's far-flung island territories or serve as a floating relief operations center in times of disaster, the vessel is equipped with just two 20-millimeter cannons and two air-defense missiles to shoot down incoming anti-ship missiles.
"Basically, it only has enough weaponry for its own defense," a Defense Ministry source told the Mainichi Shimbun. The Izumo has even less armament than regular MSDF escort vessels, which have anti-ship and anti-aircraft weapons, leaving another ministry official to wonder if "there isn't a large element of showmanship" in the helicopter carrier's new mission.
The Japanese government had been considering ordering an MSDF escort mission for U.S. warships sometime this year, and the U.S. apparently strongly requested Japan provide protection for U.S. Navy ships as tensions rose with North Korea. MSDF vessels conducted joint drills with the Carl Vinson strike group east of Tsushima Island on April 29 but did not carry out escort duties. The MSDF vessels were apparently not assigned to protect the U.S. carrier because the strike group already has a number of Aegis vessels capable of doing the job, and having the MSDF ships escort U.S. military vessels in waters near the Korean Peninsula risked provoking North Korea.
If Japan wished to protect U.S. ships from North Korean missile attack, then the MSDF's own Aegis ships would be best suited to the mission. Nevertheless, the Izumo, which is also scheduled to join an international naval review in Singapore starting on May 15, was selected for escort duty.
It appears that the Izumo, one of the MSDF's largest ships, was selected for escort duty more for its visual impact than its defensive strength. However, protecting U.S. vessels with the Izumo and its advanced submarine-hunting capabilities may also be aimed at checking China's maritime advancement using its growing naval capabilities, including in its submarine force.