@Bltizo
Couple of other comments.
Another way of looking at it, is how likely is it that China will need to launch a lightning strike against Guam out of the blue?
For the next 20+ years, China's economic and military potential should continue to rise much faster than the US and its allies.
And China is the world's largest trading nation, depending on imports of raw materials and exports of manufactured goods. Most of this trade is seaborne.
A war would likely derail China's economic plans, which is why some in the US advocate a war with China now, before China achieves military/economic superiority over the US.
And look at the latest news where Trump thought China had a hurricane weapon that could be used to secretly attack the US, or how Trump wanted to attack other countries but blame these attacks on China. The worrying (and depressing) thing is that Trump is likely to be back as the US President in a few years.
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And assuming there is a period of tensions beforehand, one would expect Chinese submarines to be surged as a warning or in anticipation of a US declaration of war against China. So if China has 60 SSNs with 12 on patrol at any time, that means another 30+ ready for surge within a few days. So it would be better for those 12 SSNs to be patrolling further afield, and to rely on the surge boats to flood the waters around Guam and the 1st/2nd Island Chain.
One would hope that in such a scenario, the US would take it seriously.
Remember that the objective is to deter the US from interfering in the Western Pacific, not to actually go to war with the USA and have to defeat them in a war of attrition.
