I'm honestly not sure what the obsession is putting capabilities on ships that don't need them.
There's a
joke among some defense analysts and PLA watchers. There are actually at least a couple versions to it. Regardless, it might be applicable to our discussion . . .
From a Chinese perspective: "Whatever the Americans have, we should have too." (美国人有的，我们也应该有。)
From an American perspective: "If you want to know what the PLA is working on just figure out what the DoD is funding." Though the opposite is increasingly true too, especially these last few years.
This is obviously a
gross generalization, but for a variety of reasons there's
substance to the
joke.
Ultimately, the Chinese most likely recognize combining auxillary nuclear power with a vertical launch system as
one way to make PLAN SSKs more akin to SSNs in terms of capabilities and doctrine, or perhaps even the
path of least resistance
towards an "all nuclear fleet."
Disclaimer: By no means am I saying the Chinese are copying the Americans. That's a silly and oversimplified trope, and factually untrue in this instance. However, we'd have to be stupid to deny that the USN sets the bar in terms of submarine warfare, and it makes sense for the PLAN to aim for similar capabilities.
What is the role of a mini-nuke? What do you need it to do?
Fleet composition is just as important factor in determining platform capabilities as everything else. Trying to stuff as much capability as possible in a platform is procurement mistake.
From my limited understanding the Chinese have made significant strides in UUV technology in recent years, and not only operate unmanned platforms that are capable of laying mines and deploying sensors, but also firing torpedos against enemy vessels.
Manned submarines are not going away anytime soon, but the
emergence of UUVs inevitably diminishes the role and value of the PLAN SSK fleet for certain missions.
Naturally, as a
bureaucracy,
the PLAN is going to find new missions for its SSK fleet (or whatever it is to be called), if for no other reason, to keep its sailors employed and its budget flowing. Incorporating a VLS is one way to accomplish that, especially an UVLS of some variety that's compatible with a multitude of missiles for a variety of missions.
China's fire power is overwhelming within 2IC through DFs and aerial assets. But a few VLS/ on mini-nukes don't bring much.
The PLAN isn't going to let the PLARF have all the fun, if for no other reason, for the sake of its own relevance as a sister service competing for funding. The CMC also isn't going to want all its eggs in a single basket.
The KSS-3 is the biggest sub in South Korean arsenal. An increased sprint endurance is far more valuable to PLAN than a few extra VLS it can't deploy rapidly.
Building "SSN-like SSKs" makes sense, especially as UUVs undertake more missions previously performed by SSKs.
How else would you expect relatively larger SSK platforms, with "next generation" AIP technology, in PLAN service or elsewhere to evolve in terms of capabilities?
