With Friday's announcement of the new National Defense Program Outline, however, the SDF is on the verge of being transformed into a military ready to go to war in the event of a terrorist or missile attack.
The forces are also expected to play a greater role in improving international security.
"It's a time of operation," Hajime Massaki, chief of the Joint Staff Council, said Thursday. "Up to now, we have engaged in training to serve as a deterrence. But from now on, our capabilities will be tested."
By specifically naming China and North Korea as threats to national security and pledging to revamp the SDF to counter them, Japan's security policy is becoming that of a normal state, observers say.
The Japanese constitution's Article 9 forbids Japan from having a military:
ARTICLE 9. Aspiring sincerely to an international peace based on justice and order, the Japanese people forever renounce war as a sovereign right of the nation and the threat or use of force as means of settling international disputes.
In order to accomplish the aim of the preceding paragraph, land, sea, and air forces, as well as other war potential, will never be maintained. The right of belligerency of the state will not be recognized.
However, the government's interpretation of Article 9 allows for purely defensive forces, and the Japanese Self-Defense Forces, including the Ground SDF, Air SDF, and Maritime SDF, were established in 1954.
The controversial part of these most recent changes will be the SDF's increasing cooperation abroad with the US military. The Japanese supreme court has interpreted the constitution to mean that Japan may defend itself, but it may not exercise collective defense. That means that Japan cannot defend an ally from attack.
For example, the Coalition invasion and liberation of Afghanistan would be an act of collective defense. The US was attacked, and its allies formed a coalition and acted against the aggressors. When Japan sent SDF supply ships to refuel Coalition war ships participating in the invasion, did Japan join in this act of "collective defense"?
At what point does a nation cross over from supporting an ally to acting in collective defense?
This is one part of a significant debate going on in Japan right now, about which I'll write more at another time.