Disagree. Just about every item of equipment the US military needs is transportable by air. C-5's and C-17's can take M1's for example (probably the heaviest load). It is just not practicable to do so unless time is of the essence (think opening phases of Desert Shield - and even then I don't recall many if any M1's being air landed).
Marc, as I recall it took the USA six months to concentrate forces for the DESERT STORM. Clearly C-5's and C-17's are not enough. CAMP RHINO was established by an air assault, but Marine. If air transportation was sufficient, and the USA has more than most, why truck stuff through Pakistan from the coast?
What's the point of your question? Did the allies 'stuff up' by not having an all marine force because the invasion was a contested landing? Frankly the marine corps are just grunts with a specialised set of equipment and manning scales to perform certain roles better than regular infantry who lack the seagoing toys. Same goes for armies that have 'mountain units', or paratroopers, or arctic warfare specialists etc. Wih the right equipment and training a force can perform whatever role it needs to - as we don't have the luxury of massive numbers wearing green I think we do pretty well with the existing light conventional structure. It is the jack of all trades/master of none approach - but it works pretty well for us.
That's the problem though. National security doesn't work on the "jack of all trades/master of none approach" principle. There is a thing called Strategic Guidance. Within it the ADF is directed to acquire Expeditionary Operations capability. Part of that capability is to enable land entry when the ordinary infrastructure points of entry are denied or unavailable. This leaves the beach, and at least a 50/50 chance it would be defended.
The role the grunts are supposed to fill, and the equipment they need, should reflect at least the most likely environment they will need to perform in. In the spectrum of all environments you listed, neither the arctic, airborne of mountain seem to me to figure prominently in the Australian region of influence or interest, but the possibility of being "seagoing" tends to occupy a large slice of that spectrum.
Doesn't every equipment procurement start with establishing the proposed capability need? Clearly the USMC felt they had the need for assault, and now they are "refocusing" towards Asia-Pacific. So I guess ADF has a different insight into the Asia-Pacific security environment over the next 40 years to that of the major Ally.
When I was in 6RAR we seemed to do pretty well landed across a beach in USMC AAV7's, were given some kind of mythical Chindits/supermen reputation for a night raid behind enemy lines on exercise in the states and still didn't need to wear our jocks on the outside. If as you suggest we optimise our force equipment toward being a Marine Corps first, then that will entail compromises that may make us less effective in other phases of warfare. Placed side by side any decent swimming amphibious APC/MICV is going to have a larger footprint than say a Bradley/Puma/Warrior. As such it will probably result in greater casualties in the larger vehicles than in the more purpose designed non amphibs. I'd rather see Aussie M113's replaced by Puma than AAV7's (or EFV's had that gotten a guernsey). Any 'assault' by Australian forces would most likely be unopposed or very lightly opposed - Puma's will land very well from LCH's - and when ashore be far more survivable than a design compromised by swimability.
I certainly would not suggest the Australian Army adopt USMC equipment. Its not designed to do what the USMC is purportedly supposed to be able to do. The Bradley/Puma/Warrior designs were not of course entirely useful even during the
Cold War, so certainly not now.
I don't claim the ability to predict 40 years in future. Of course c.1902 no one in Australia thought their sons, brothers and fathers would be combating Turks in a decade and a bit (Boers were a surprise enough), or the Japanese in New Guinea in 1942 (we were still waiting for the Russians!).
I dare say that when the first time RFI was issued for the M113 replacement in 1980 there wasn't one Army officer that contemplated the design's usefulness in Somalia. Lucky that Tobruk had prior experience with poor wharf facilities in the Pacific. Many US ships couldn't unload at all, and just went back to Diego Garcia.
But, for the sake of Australians in uniform, I hope all their assaults are unopposed or 'lightly' opposed. Any 'well done' assaults, would be murder.
All I see is a World with a lot more PGMs.
As for the design being compromised by swimability, perhaps you suggest that the PUMA ICV flies to the beach?
Between the LCH and the BLZ, there is the LCM, still compromised by swimability, which is a part of its functional design engineering requirement.
Or maybe you suggest that the SOFs assault the beach to clear the way?
I also hope that when the Australian Army get the Puma, they choose their deployments carefully so the terrain closely matches that for which it was built, Germany.
Interestingly in May this year CRS reported that one of the designs for the the US Army GCV was by the SAIC-led team based on the Puma IFV that was developed based on lessons learned from Iraq and Afghanistan. It was rejected after a protest. Perhaps because every war tends to deliver its own unique lessons? One doesn't go to lessons for lessons' sake, but to get a degree. The same report identified that other than the Israeli Namer, none of the foreign "off the shelf" vehicles can meet the GCV requirement to accommodate a nine-soldier squad.
But, this isn't the real problem. I'm sure the Puma is a finely engineered Scherman design.
The problem for me is that its a defensive design. It was designed for the Cold War, and the Cold War is over.
It was not designed for expeditionary operations.
Expeditionary operations are generally considered manoeuvre warfare, and therefore offensive. Particularly, the pre-emptive strategy is suggested, that can generate the element of surprise. It suggests agility, flexibility, ease of deployment, etc. To me the PUMA doesn't seem that sort of a system.
Worse, the Puma is designed for a very different logistic set up, not tied to a support vessel. That fine MTU engine is going to need a lot of juice crawling around rain-sodden Asia-Pacific soils, don't you think? Or do you see the 6RAR somewhere less well served by seasonal moisture content?