The problem is that in a major conflict like that using SRBMs or MRBMs with conventional warheads would not be cost effective.
Let alone ICBMs or the likes. I doubt China even has conventional warheads for ICBMs.
The V-2 was not effective because it had little accuracy and next to no destructive potential in relation to its cost.
You will have to take cost benefit into consideration when you use those missiles. So let us say you use the tactical nukes to hit US bases in the Pacific or carrier groups. I think that would be the most likely scenario.
If we're talking about SRBMs or MRBMs, the ranges are up to 2000km or so.
The majority of the 1st Island Chain lies within 1200km (eg. all of Korea, Japan, Taiwan and half of the Philippines)
That is workable distance for aircraft to launch regular strikes using lower cost munitions, after any initial missile strikes.
And if we look at the maths for IRBMs and ICBMs, the approximate costs are as follows:
ICBM ($60 Million) versus ($75 Million) per GMD interceptor x2
DF-26 IRBM ($21 Million) versus ($11-18 Million) per THAAD interceptor x2
Then you have the costs of the ABM radar and other equipment. A THAAD battery with 48 interceptors costs up to $3 Billion in total
So missile strikes do generally work out at all levels ie. SRBM, MRBM, IRBM, ICBM.
Particularly if they are used against airbase runways and/or use cluster munitions to destroy any large aircraft on the ground.