By Jonathan Head
BBC News, Tokyo
Japan's military has been placed under a new unified command to make it responsive to possible threats.
The changes follow Japanese deployments to the Persian Gulf
The land, sea and air self-defence forces hope the joint command office will smooth co-operation with US forces in the Pacific.
The self-defence forces will still not be called an army, navy or air force.
But the more streamlined command structure shows the military is in the slow process of changing into something akin to the forces of other countries.
Much of the change is happening at the behest of the United States, which is encouraging its closest ally in Asia to shoulder more of the burden of regional security.
But there has been a shift in the attitude of the Japanese people as well, in the face of missile threats from North Korea and the growing military strength of China.
That is why opposition has been muted to the deployment of Japanese forces to Iraq and the Persian Gulf.
But it is partly the experience in these overseas deployments that has prompted the creation of this new command structure.
In the future, Japan plans to develop a joint missile defence programme with the US.
It expects to join future multi-lateral operations abroad and to increase its capabilities at home to allow the US to reduce its military presence in Japan.
This is all part of what the government describes as turning Japan from a peace-loving to a peace-supporting nation.
Despite the changes, commanders will still wear civilian clothes on their way to work, switching to uniform only once they are inside the defence forces headquarters.
Japan's constitution will also still bar the country from waging war.