This would definitely add to Japan’s ability to launch offensive strikes if developed. However, this is something that is going to take many years to develop and build:
Moves are being made to build a submarine to examine the technical issues faced in deploying ones capable of firing long-range missiles, Japanese government sources have said.
The development plan will be included in the National Defense Program Guidelines to be revised by the year-end.
If the development progresses for actual deployment, Tomahawk cruise missiles that the government has approached the U.S. government about purchasing will be an option for the vessel.
Stars & Stripes
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