I think that's a perfectly legitimate concern to have. And, quite frankly, I've never actually seen the (mainly Army) concept of forward deployed land based missiles actually genuinely considered, or argued against.
Where are those forces going? Many of the neighbours we casually throw around have a very different relationship with Beijing. They are not going to want to be dragged into a major regional conflict between the US and China. The uncontested idea that we can park on Indonesian, Malaysian etc territory and shoot at PRC targets is not an assumption I would grant a Staff Cadet at RMC, let along Russell Offices. Some nations may - PNG for instance - but what does that achieve for us? Defending our north-east quadrant is great for us, but what is it achieving from a PRC point of view? Are the PRC even going to send surface vessels to the Coral Sea when they are in the fight of their lives around Taiwan?
How are those forces getting there? The closer we go to the PRC, the easier it is to target our forces and the more options the PRC has to throw at us. The options they have to strike Guam v Darwin is literally orders of magnitude. So how do we get these missile launchers there? Note also, the PRC doesn't have to strike the strategic lift. It can just track them. Someone mentioned Gull and Sparrow force above - they all died. For nothing. you cant hide the deployment of these beasties.
What are you taking? Some Strikemaster? Bahahahahahahaha....... that's murder. Such short range weapons are a joke. So HiMARs or better. Cool. Note at the moment that's still well within the PRC WEZ, but the best (land) option we have at the moment. So, what, a Battery of HiMARs? That's 14 launchers. 14x PrSM missiles. Ok.....I mean, that's less than the Tier 2 combatants we were going to buy, but sure. Not sure it's going to do anything - the PLA-N is designed to fight an enemy with 122x VLS Ticos, 96x VLS Burkes and multiple CVNBG.... I'm not sure what 14 extra missiles are going to do (not nothing, but still....).
How are you going to protect them? I mean, you don't have to. You can leave them to die. But they will need protection. Their disembarkation point is known. The number of launch points worth of PRC attention is known. They are closer to the WEZ than anything else, so the PLA have even more options than striking Australia. This rapidly turns into a significant chunk of ADF power, dangling out .... 'there'
The advantage China has, is that Australia is negligible. We are not a threat. Anything worthy of striking here (which is Stirling and maybe a RAAF Base where a heavy USAF presence is) is geographically known (as opposed to a PLA-N SAG) and is already in range of multiple Chinese options. So the issues facing us, targeting, range, missile production rates, simply aren't an issue for Beijing. Their challenges in those areas relate to the mobile targets east of Taiwan, specifically the USN units. The only possible similarity facing Beijing is the ABO issues, but they already have long-range missiles and they travel out of the atmosphere - negating ABO. Furthermore, the possible diaspora to hide non-conventional forces in is in Beijing's favour, not ours.
I've been arguing against Army owning anti-ship missiles since writing the first needs statement in 17/18. Lessons from the Baltic and Black Seas don't apply here. It's a waste of resources - if you want an anti-ship capability you fund the RAAF and RAN. They do it better and faster. The reason I'm a HiMARs fan is because it's the beginning steps to a genuine very long range strike capability, preferably hypersonic. The PrSM plan gets us most of the way, and hopefully by then we have options to go beyond that. Then we can shoot from Australian territory at the things that matter.