TOKYO -- Japan's Maritime Self-Defense Force has been refueling U.S. vessels keeping watch for North Korean missile launches, a first under 2015 security legislation that has enabled broader military cooperation between the two countries.
MSDF supply ships have provided fuel about once a month to American vessels equipped with the Aegis missile defense system in the Sea of Japan and elsewhere, at the U.S. military's request, Japanese government sources said.
The legislation, including revisions to the Self-Defense Forces Act, expanded the range of circumstances under which the Japanese defense forces can supply U.S. troops, adding missile defense and anti-piracy activities to a list that also includes joint drills. The refueling operations began after necessary changes to the bilateral acquisition and cross-servicing agreement took effect in April.
The 2015 legislation also let the MSDF take on other support duties. A Japanese warship escorted an American supply vessel in May.
The MSDF previously supplied U.S. and other ships with fuel in the Indian Ocean between 2001 and 2010 under temporary legislation permitting Japanese forces to support anti-terrorism operations in the region. That experience has likely been put to use here.
North Korea's recent missile tests have forced Aegis-equipped American and Japanese vessels to remain on alert around the clock for further launches. Having the MSDF supply fuel to U.S. ships at sea saves them the trouble of docking to refuel, a time-consuming process that would leave temporary gaps in Japan's missile defense network.
Another aim is likely to speed up the process of unifying the operations of Japanese and American forces to present a stronger deterrent against such threats as North Korea. Since Japan's strictly defensive Self-Defense Forces lack such equipment as bombers or cruise missiles, they have to rely on the American military for offense during a conflict, such as striking enemy bases.
"We must support the U.S. military as much as possible, starting with peacetime, to ensure Japan will be reliably defended," a government source said.
Retired Vice Adm. Toshiyuki Ito praised the refueling operations as an example of closer bilateral cooperation. Questions had been raised as to why Japanese forces could supply American ships during drills but not actual missions, he noted.
No right to know?
As of Wednesday, Tokyo has not announced the refueling activities. "We can't disclose information related to U.S. forces' operations," a senior Cabinet Secretariat official explained.
The concern is that the positions of Aegis-equipped American vessels could be revealed, compromising their ability to perform their duties. "Refueling is the toughest time for ships to remain defense-ready," a senior Defense Ministry official said. "Allowing [the MSDF refueling] to be made known would cause operational problems."
The ministry says no agreement has been made to keep the refueling operations secret. But the May escort mission was also not made public, and government guidelines released last December stipulate that operations involving U.S. vessels should not be disclosed barring extraordinary circumstances.
Yet Prime Minister Shinzo Abe said during deliberations on the security legislation that the government would share as much information as possible on SDF activities and provide proper explanation. If the government keeps staying mum out of consideration for the U.S., it is possible that regional tensions could rise even as the public remains in the dark about what American and Japanese forces are doing.
And closer cooperation between the allies' forces heightens the risk that the SDF will be lumped together with the American military. Should the U.S. take military action against North Korea, the SDF could become a target as well for providing logistical support. The government must consider how much to reveal when informing the public.