TOKYO -- The Japan Self-Defense Forces have averaged two joint drills weekly since January, reaching beyond longtime ally the U.S. to include fellow Quad members Australia and India as well as European nations.
On the other hand, Tokyo has not conducted a drill with South Korea since 2018 as a chill has fallen on relations between the two neighbors.
The Self-Defense Forces have carried out 38 joint exercises with foreign militaries from January to May, according to public announcements. Aside from the Quad -- formally the Quadrilateral Security Dialogue -- European countries have noticeably taken part in multilateral drills in recent years.
France led an April exercise in India's Bay of Bengal that included Japan's Maritime Self-Defense Force as well as the U.S., Australian and Indian navies. The training sent a message that Europe and the Quad are united on deterring China.
Japan's Ground Self-Defense Force conducted island defense drills the month after in Kyushu -- to the country's west -- alongside American and French personnel. The Air Self-Defense Force did two joint exercises in airspace above the East China Sea with the U.S. in April alone.
The flurry of joint drills marks a rise from a year earlier, when the pandemic disrupted activities. March 2020 had zero joint exercises, while April and May of that year only had two drills each.
The joint exercises began to pick up last summer after infection prevention measures were put into place.
Since January 2020, Japan's Maritime Self-Defense Force has participated in 69 naval drills -- the most among the three SDF branches. International waters are a convenient location for military personnel other than U.S. service members stationed in Japan. Nearly half of the 69 naval drills brought in non-U.S. forces.
During the same period, Japan's Air Self-Defense Force participated in 28 joint drills, while the Ground Self-Defense Force took part in nine. About 90% of the exercises were bilateral affairs with the U.S.
Fighter jets and ground units are difficult to transport over long distances without resupplying, so ground and air joint exercises feature mainly American personnel stationed at Japanese bases.
Joint drills are a barometer of diplomatic relations. Looking at joint drills since 2012, including three-way exercises with the U.S., participation by Australia and India have jumped conspicuously.
Japan carried out seven to 10 joint drills apiece with Australia and India in 2019 alone. Tokyo sees the latter as like-minded countries when it comes to maintaining a "free and open Indo-Pacific."
But Japan has not held a joint exercise with South Korea since 2018. Then-U.S. President Donald Trump shifted course that year to opening a line of dialogue with North Korea. The two American allies have avoided multilateral drills against that backdrop.
Distrust between Tokyo and Seoul has not helped. A South Korean warship locked its fire control radar on a Japanese surveillance plane in late 2018. Disputes over wartime "comfort women" and labor issues have chilled relations and caused defense exchanges to stagnate.