Japan likely to discuss possessing nuclear subs

The ruling Liberal Democratic Party and Nippon Ishin no Kai (Japan Innovation Party), as part of their coalition agreement in October, pledged to promote the country's possession of submarines powered by a next-generation energy source and equipped with a vertical launching system, or VLS, for long-range missiles.

Defense Minister Shinjiro Koizumi said on television on Thursday that "the environment surrounding Japan is so severe that we have to discuss whether to use diesel as we've done so far or nuclear power."

The Maritime Self-Defense Force currently possesses submarines powered by diesel engines and lithium-ion batteries, which make it necessary for them to regularly surface and take in air to recharge batteries.

Nuclear submarines do not have to do the same, enabling them to stay submerged for a long time.

A VLS can only be equipped on a submarine with a large hull and high mobility.

Speed is important to avoid counterattacks, because the location of the submarine will likely be detected by the enemy after a missile launch.

At least three nuclear submarines need to be introduced for a routine of maintenance, drill and mission.

The maintenance cost of three nuclear submarines would be huge, so their introduction would require a review of the structure of the MSDF, which struggles with serious shortages of personnel.

The MSDF also needs to secure nuclear engineering experts to deal with possible radiation leaks.

Some say that officials need to revise the country's atomic energy basic law, which stipulates the peaceful use of nuclear power, or at least change its interpretation.

The understanding of locals in possible homeports and anchorage sites is also necessary.

A Defense Ministry official said that "the introduction of nuclear submarines has been a taboo subject in the SDF for a long time and has not been properly discussed," adding, "It depends on whether politicians are ready to decide."

Another ministry official said, "If it is only to monitor and deter China and Russia, it is enough to protect areas around Japan, so I wonder whether nuclear submarines are really necessary."