> I'd be shocked if nano-augs weren't completely dependent on at least a lifelong course of immuno-suppressants
People talk about what kinds of nanotech would be the easiest. Probably the easiest would be to very slightly modify nonhuman biological systems. We do have the tech to fiddle with genes. It's not impossible to get a tomato plant that thrives in salty soil, for example.
If we could have much more precise control over that type of biological modification, we would have "wet nanotech."
We don't have "wet nanotech." We would need to be able to do "wet nanotech" before we could do "dry nanotech." We would want "dry nanotech" to be able to do the fancy impressive stuff, such as real nanomachines worthy of the name. I suspect that "wet nanotech" augs might be friendly to human physiology, but "dry nanotech" augs would require immunosuppression or similar tweaking.
Smart materials (e.g. diamondoid threads) are a reality in the lab but are too expensive to mass produce at present. A practical nano-trooper would probably be a standard trooper wearing diamondoid armor instead of kevlar armor.
The elephant in the room is that we already have super-soldier serum, in the form of amphetamines and steroids. However, Western culture has a massive taboo about drugs. Thus Western countries are not likely to conduct enough experimentation on amphetamines and their derivatives. Thus Western countries will continue to use various stimulants on their troops (e.g. modafinil) without truly understanding the biology.
Thus, even if we got enough nanotech to do nano-augmentation, we would be too ignorant of biology to design the immuno-suppressants that would allow the nano-augs to function.
However, the West could continue to wage the War on Drugs indefinitely. War is profitable for a small number of profiteers.