Next month will mark one year from the announcement of the "dynamic joint defence force" concept, in which Ground, Maritime and Air Self-Defence Force operations will be more closely integrated to handle the worsening security environment surrounding the country.
Though the reinforcement of cooperation among the Self-Defence Forces is necessary to improve defence capabilities on remote islands, there are still many challenges to overcome, such as differences in systems, equipment and mindset.
On Amami-Oshima island in Kagoshima Prefecture, the Ground Self-Defence Force's Type-88 surface-to-ship missiles, loaded on trucks, were being prepared for launch at enemy ships approaching.
On a nearby uninhabited island, the GSDF's unit to defend remote islands was engaged in an operation to recapture the island after a boat landing.
Those were the scenes from a Japan-US joint drill, named Keen Sword, and related drills implemented from Nov. 8 to 19, involving about 40,000 personnel from the two countries.
Based on a scenario of armed attacks on islands, Self-Defence Forces have checked steps to prevent an invasion by enemy ships or aircraft, sending troops with support from US forces.
The drill is carried out every two years, but this was the first since the concept of a dynamic joint defence force was announced.
As a senior SDF official said, "Cooperation among the three Self-Defence Forces is essential for island defence." The drill this year had smooth cooperation as its focus.
"We successfully improved the capability of operating troops," said SDF Chief of Joint Staff Katsutoshi Kawano at a press conference on Nov. 19.
However, there were issues needing to be solved here and there during the drill.
For example, although antiship missiles that can strike enemy ships on approach are the ace in island defence, they cannot be used against ships on the open ocean despite their range of more than 100 kilometers because the GSDF has only ground-based radar. The establishment of a system to automatically share information obtained by MSDF aircraft in the sky has just begun.
On the beach of Amami-Oshima island, a drill was also carried out to set up a makeshift dock on a remote island recaptured by the GSDF.
Though the dock is for MSDF transport vessels to land vehicles and goods, it remains unclear how to land cargo as remote islands in reality are surrounded by shallow waters which are unapproachable for transport vessels.
"We are thinking to purchase a large float to relay cargo. The three SDF forces are working by trial and error at the sites," an SDF senior official revealed.
The call for integrated operations between the three Self-Defence Forces indicates that cooperation had until recently been insufficient.
As the three forces have been developing independently, they originally had different operation plans, equipment standards and terminology.
Though the Joint Staff was launched in 2006 with the aim of operating the forces integrally, it is not easy to take down fences between them, as was seen in a case during the 2011 Great East Japan Earthquake disaster when GSDF troops could not communicate by radio with an MSDF vessel that was in front of them.
They are also rivals in terms of competition for a limited defence budget.
While a GSDF senior official said proudly, "We are the final line of defence that protects our land," senior officials of the MSDF and ASDF have said that it is acceptable to cut the GSDF budget as their own services can prevent invasions in territorial air or waters, showing their deep-rooted rivalry.
To achieve integrated operations between the forces, the Defence Ministry will carry out capability evaluations to assess shortcomings and improve defence capability based on the results. It also plans to take measures to eradicate barriers, aggressively transferring competent senior officials to the Joint Staff.
Yoshifumi Hibako, former head of the GSDF who undertook disaster-relief operations as the head of the force at the time of the Great East Japan Earthquake, said: "As islets of the Nansei Islands are scattered over a vast expanse of water, we can hardly respond to emergency situations and great natural disasters unless we intensify integrated operations.
It is important to promote better understanding among personnel by increasing opportunities for joint exercises and study tours for troops."