@skywatcher: sorry I was never particularly advocating for putting these in tunnels I was primarily considering whether a system could be made mobile. But if chinas tunnel system can handle ICBMs I can't see what it can't handle similarly large TELs with a gun.
Also, while I agree that self propelled/TEL cannons are better than towed, it may not matter very much if the cannons are under IADS (the cannons in a single battery could be dispersed over a wide area too). In any case I cannot see this system being used in a scoot and shoot way.
@chuck
What? You're saying to target a missile system you need to take out just the missile on the TEL, whereas for a gun system you only need to take out the gun? I'm not sure which you are advocating as more vulnerable. Both a gun and missile system/battery includes more than one TEL/truck and there are a variety o support vehicles too. And all can of course be dispersed over an area. The only advantage I'd offer missiles is that they don't need reload vehicles I accompany each individual gun in the company (or them again, they might, considering we've seen reload vehicles follow PLA SRBMs around). Of course the difference is a gun reloading vehicle can carry far more rounds given each round is smaller than an SRBM
I am saying with a missile system, of course youe would disperse the TELs. So in effect, the enemy has to target every booster separately to terminate the threat. If there is no MIRV, that means you have to target every warhead separately.
With a gun, the gun is a big capital investment, and obviously you won't have as many guns as you can have missile boosters, and any gun 110 foot long would be hard to make mobile and disperse. So you only have to take out the guns.