In the security legislation envisioned by the government, "situations requiring the mobilization of the Self-Defence Forces" are divided into five major categories.
Of the five, the most serious is an "armed attack situation" targeting Japan, or an actual military contingency directly affecting this country. In such a phase of a crisis, SDF personnel will be mobilized to protect the nation from the attacks.
In a phase prior to this, or a "situation in which an armed attack on Japan is anticipated," measures will be taken under the new legislation such as building defensive positions and evacuating residents in the areas involved. These actions have already been included in the Self-Defence Forces Law and related laws.
Newly included in the planned security-related legislation, in addition to armed attacks on Japan, is the concept of a "situation that threatens Japan's survival." This means Japan can mobilize SDF personnel in the event there is clear danger of an armed attack on another country, such as the United States, that threatens Japan's survival.
To be either altered or newly created in the security bills are the remaining two categories of situations, defined either as a "situation that could significantly affect Japan" or a "situation requiring a joint response for international peace."
Japan's logistic support for US troops or others coping with armed conflicts in such areas as the Korean Peninsula and the South China Sea is envisioned in the "situation that could significantly affect Japan."
A situation requiring an international joint response action refers to sending SDF personnel overseas in support of multilateral forces' activities based on a resolution of the United Nations. Activities such as the refueling support the Maritime Self-Defence Force carried out for vessels of multilateral forces in the Indian Ocean would be covered by this category.
The two categories of situations are stipulated in the two separate government-envisaged security bills.
The government says if and when an armed conflict breaks out, it will decide, on a case-by-case basis, which one of the situations should be recognised in light of the five-category conceptualization.
Given that it is impossible to clarify in advance which conflicts will fall into which categories and which laws and regulations should be applied to an unfolding situation, the issue of what judgment should be made on the matter will most likely be extremely complicated and difficult to understand in the eyes of the public.
With Japan's sea-lanes, or international maritime lines of communication, being blockaded by mines, for instance, four of the five supposed contingencies could be applied, depending on the nature and degree of the impact the situation in question would have on Japan's peace and security.
A "situation requiring a joint response for international peace" has no direct impact on Japan. However, should the situation then develop into one that would impact Japan via soaring prices of crude oil, the concept of a "situation that could significantly affect Japan" could be applicable.
Furthermore, a situation such as that in which danger looms regarding Japan's oil stockpiles being depleted could be recognised as a "situation that threatens Japan's survival." Should conflicting countries begin military activities in seas near Japan, the possibility could arise of the situation being considered a "situation in which an armed attack on Japan is anticipated."
Since the SDF's specific activities and procedures for prior approval of the Diet will differ according to the different categories of the situations, the act of recognition of the situations will most likely be left up to the high-level judgment of the nation's political leadership.