"The language's direct effect on fault tolerance is not always easily measurable. Even in C you could add compile-time instrumentation to discard invalid writes and redirect invalid reads to fixed-size buffers (failure-oblivious computing) and that's just a proactive measure."
I think you're going too far with it. Stuff like that is covered in fault-tolerant and immunity-aware computing. Most straight-forward approach is a NonStop-style system or TMR with voting. However, getting that far for fault-tolerance and security is way, way beyond standard practice. I'm just asking that standard practice move beyond the same old, same old problems. The baseline would be so much better and we could then work on the next leap. Not to mention the infusion of money and effort into tool support for that would greatly benefit high assurance work that tries to address what you're talking about.
"ince we can't get that, but instead mostly rely on cargo culting like "Haskell is magic pixie dust because math" for our software safety and availability, I find the prospects of careful HA research (which is more mathematically rigorous) to be daunting."
Best to think of it as several processes or systems working in lock-step one function or major state change at a time. That's been deployed in academia and commercially in many ways. There's even tools to draw on to help. Treating the system as a whole black box with restarts at failure simplifies things. This way, they can keep their pixie dust.
Meanwhile, we make the pixie dust better. Memory-safety, type-safety, and concurrency safety by themselves knock out most of what does damage. Hardware enforcement of these for CPU and I/O interactions make attacker's job daunting. A great exception system will help, too. The next steps are Design-by-Contract, automated test generation from those specs, static analysis with no false positives, information flow labels a la Cornell's SIF/JIF, and continued use of cookbooks like OWASP tools. Combining the above leaves very little room for bugs to hide. At the least, attacks become so expensive and valuable that only nation-states have them. Progress, eh? ;)
"Getting that deployed is going to be an uphill battle given fault tolerance's neglect"
It's happening a lot in mobile and safety-critical embedded. Virtualization, esp security-centric, has already taken off. I think modifying one to work with cloud-stacks and piggybacking off them might help. Might drop it to medium assurance due to complexity but would be improvement. Can structure it and assure it like VAX VMM Security Kernel did with modern tools/analysis. I doubt we see mass market uptake but a niche market might pick it up if cost/benefit still looks good.
"I think you overestimate public resistance to surveillance. The Church Committee came and went quickly, and was forgotten and dismissed over the legislative band-aids that people blindly believed were as effective as that."
It was more about major abuses than surveillance. I have little faith in public on the latter. We at least got to see a lot of details on things like COINTELPRO that are important in countering the propaganda. Point was that action was taken, some kind of result happened, and their level of domestic abuse appeared to drop a bit. Another good example was increases of FOIA power at different points, which helped us many times in the past. We didn't really need major results from Snowden leaks to deal with NSA, etc. Might have been as simple as eliminating bulk, forcing FISA warrants for targeted collection on Americans (not collection criteria), ability to challenge that in court (no parallel construction), and a clear indicator that no company/individual can be compelled into backdoors. Just four points could go a long way to knock out biggest legal risk with private sector and nonprofits handling the rest.
What we got instead was no response on... anything. I was less bummed about NSA than 2008 financial crisis. Over here, Wall St gets $1+ trillion, no questions asked, and immunity. Over in Iceland, they overthrew the corrupt machine, seized the assets, eliminated questionable debts, and (given Wikileaks was source) later passed some of best press protections in the world. That is how democracy is supposed to work when facing that level of corruption. The American approach was BOHICA: Bend Over, Here It Comes Again. Has been consistently since with few exceptions. Disgusting...
I want to see Americans pull an Iceland on one of these core issues.