1st Response To "WahooDaddy" - Some Water Space Considerations

Subsurface issues concerning the South China Sea and East China Sea are very complex and interconnected with physical and human matters.

For example in Part One of August 1, 2016, I argued China's 4 to 6 x Type 094 "Jin class" SSBNs in China's "naval Bastion" between the PRC mainland and First Island Chain (see Map A below) may continue to be too limited in capability to be effective, due to:

-  geography - very shallow water around China's SSBN Base at Yulin,
Hainan Island then a restricted South China Sea operating area, then sea depths too shallow especially south of Indonesia's Natuna Islands (see Map B), 

-  094s are known to be too noisy to be as stealthy as US, UK and French SSBNs

-  PRC commanders and crews lack operational SSBN patrol experience

-  the JL-2 SLBMs missiles with a range of around 8,000 km are too limited to hit US mainland targets from the protected (near Chinese) waters the SSBNs have to operate in. 

-  JL-3 SLBMs of the mid 2020s with a 10,000+ km range that might reach the US mainland can apparently fit in 094s

-  China's military-political command and control system may not be flexible enough to allow SSBN commanders to carry armed JL-2s or JL-3s or deliver the codes commanders to launch. Basically against Communist Party's tight control of military.

Map A above - The inner "J" indicates China's "First Island Chain" is where China's four Type 094 SSBNs are effectively restricted. These SSBNs are based in China's South Sea Fleet bases (Map A above) specifically at Sanya/Yulin Naval Base on Hainan Island. Moving outside that chain would take SSBNs away from protective Chinese aircraft and these SSBNs would need to pass between island narrows where undersea sensors (see Map C) and enemy aircraft, surface craft, SSKs and SSNs are likely to be waiting.
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Also the following could intervene into the South China Sea to destroy Chinese SSBNs: enemy aircraft and submarines from Vietnam, Singapore (passing through the Philippines) also submarines further out from Guam, Japan, Australia, Hawaii and US West Coast. 

Map B above - The water (ideally 1,000+ m deep) restricts the already narrow South China Sea operating area and the sea becomes radically too shallow (less than 100m deep) south of Indonesia's Natuna Islands.
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Useful water depth for a submarine could be all the way down to "crush depth" which may be 1,000+ meters for a Chinese SSBN. While deep water past crush depth (maybe 1,000 meters) may not benefit a submarine there is a correlation between depth and usable surface area.

The lack of adequate 1,000+ meter depth in large areas of the 3,500,000 square kms South China Sea may limit usable SSBN operational area to less than 2,000,000 square kms.

This reduced area to cover with sensors makes it easier for the US to lay seafloor or tethered sensors (including IUSS SOSUS) in and around that reduced usable SSBN area.

Tethering means that even in a 2,000 meter deep area a sensor with a 1,200 meter long tether (from the seafloor) would be very useful detecting Chinese SSBNs.

Map C above - Map depicts some of the likely Western SeaWeb IUSS 
undersea sensor array positions. Chinese, Russian and North Korean submarines and surface vessels are likely to be of most sensor interest. (Map from page 54 “Map 4. The US ‘Fish Hook’ Undersea Defense Line” of the late Desmond Ball and Richard Tanter, The Tools of Owatatsumi Japan’s Ocean Surveillance and Coastal Defence Capabilities (2015, ANU Press) http://press-files.anu.edu.au/downloads/press/p309261/pdf/book.pdf?referer=444 . 
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FURTHER COMMENT

I've made many generalisations that might be disputed by reading other websites and documents including:

-  http://thediplomat.com/2015/05/strategic-warning-and-chinas-nuclear-posture/

-  US DoD's "Chinese Military Power 2016") large PDF at:
  http://www.defense.gov/Portals/1/Documents/pubs/2016%20China%20Military%20Power%20Report.pdf

-  China's Defense White Paper 2015

-  rightwing US and most Taiwanese websites should be treated with caution as they might tend to exaggerate China's SSBN "threat" as being serious and current.

China may take 25 years to attain the quality of US, UK and French SSBNs of today and to develop a JL-3 or a JL-4 SLBM with the range and accuracy of the Trident II SLBM.

Also see: 

https://gentleseas.blogspot.com/2016/08/chinas-ssbns-limited-by-opposing.html Part Four

https://gentleseas.blogspot.com/2016/08/chinas-current-ssbns-limited-by-their.html Part Three

https://gentleseas.blogspot.com/2016/08/chinas-current-ssbns-limited.html Part Two

and

https://gentleseas.blogspot.com/2016/06/chinas-seaweb-undersea-surveillance.html

Pete