wispywood2344 on October 31, 2021, made some very interesting comments:
In recent years, Japan has been increasing its anti-submarine warfare (ASW) and anti-surface warfare (ASuW) capabilities in response to the expansion of the Chinese Navy (PLAN).
Japanese submarine and broader high tech projects are not well known outside Japan, so I will introduce some of them.
・There is an increase in the number of submarines [following Japanese Ministry of Defense (mod.go.jp) link string listed as "Not Secure" on my browser - beware!]
http://www.clearing.mod.go.jp/hakusho_data/2017/html/nc008000.html
from 16+2 to 22+2 [for the JMSDF “Navy”] [does “22” mean operational submarines and +2 mean training submarines?]
・Development and deployment of Type 18 torpedoes [For Soryu and Taigei class submarines, but not for Oyashio class. On the Type 18s also see.]
・Deployment of Type 12 surface [or ground] to ship missiles (12SSM) to 4 islands (Ishigakijima, Amami-ohshima, Miyakojima, and Okinawa-main-island)
・Development and deployment of Type 17 ship-to-ship missiles (17SSM)
・Replace aging P-3C Maritime Patrol Aircraft (MPAs) with P-1 MPAs [and see English Wiki on the P-1s]
・Introduction of Joint Strike Missiles (JSMs) for F-35 fleet
・Range extension of supersonic supersonic anti-ship cruise missiles (ASM-3A & ASM-3(Kai)) for F-2 multirole jetfighter fleet.
・Range extension of subsonic anti-ship cruise missiles for P-1 Maritime Patrol Aircraft fleet
・Development of subsonic stealth stand-off anti-ship cruise missiles (Launched from air/ground/ship)
・Research of elemental technology for hypersonic anti-ship cruise missiles [document has nice artwork of missiles]
and the last high tech project mentioned
・Development of hypersonic glide missiles (For use not only anti-ground but also anti-ship missions) [see artwork on page 12 on hypersonic missile’s heat signature/buildup].
By wispwood2344
[with some edits by Pete]