Russia or the separatists in Eastern Ukraine might have done this
That's a distinction without a difference.
although no-one is sure what they would stand to gain from it.
It looks like they thought it was a Ukraine military plane and were a bit too trigger happy, not realising it was a civilian aircraft until too late.
Ukraine's own military might have done it (they've done it before and denied it vehemently until it was proven beyond a shadow of a doubt).
Here's the thing: if the Ukraine were responsible, then Russia would have a vested interest in a visibly transparent investigation and be in a position to ensure that it happened. If they could convincingly portray the Ukraine as having shot down a civilian aircraft then that would significantly alter the political sympathies in the current conflict. Instead, they have done everything in their power to block it.
 Actually, given that this has happened on about 70% of my trips to the USA over the last couple of years, I can't really justify calling it unusual.
Yes, I see a problem with pot cafes. Drug use is not OK, just inevitable
What about cafes that serve coffee? You know, the beverage containing a highly addictive drug? Should we ban those too?
The issue with pot cafes is that it's hard for people to work in them without being exposed to passive smoke, but if you can address that then I don't see the difference between them and normal cafes.
I don't see a contradiction (although I'm not an American). I have no problems with people smoking, snorting, injecting, or otherwise consuming any drugs that they want. I do object if they blow smoke in public areas or leave needles (especially used ones) lying around in public places.
I would be in favour of banning smoking anything in public places (including places of work) and permitting people to take any drugs that they want in their own home. There are some difficult areas (for example, should people with children be allowed to smoke whatever they like at home around their children?) but the general rule of thumb should be that you can do whatever you want to your own body and mind, just don't do it to anyone else.
Yup. Compiling for the Burroughs architecture was easier than many segment-based systems, because they allowed segment descriptors to be placed in main memory, with the CPU responsible for tracking the value type by updating a tag. We adapt this slightly so that we only require one tag bit per 256 bits of main memory (the paper describes the implementation of this in some detail, but I'm happy to answer questions) to be able to safely store capabilities in main memory. Our design also allows normal C data structures to work as expected. You can mix C code compiled for MIPS and C code compiled for CHERI in the same binary (though you only get coarse-grained protection in the MIPS code).
The Burroughs architecture had very little impact on the computer architecture community, but was enormously influential in the design of VMs for high-level languages. One of our goals is to pull out the aspects of such VMs that are required for memory protection and put them back in the hardware, so a buggy VM has a far more limited security impact. My student's work on JNI dramatically reduced the amount of C code in the trusted computing base for the JVM implementation that he used.
The flippant answer is all that your paranoia deserves. The work was undertaken by SRI and The University of Cambridge. The funding was provided by DARPA, but that's the extent of their involvement (other than creating a program with the goal of being able to redesign any aspect of computing with security in mind).
The code is no more or less meriting an independent audit than any other open source code. Less, actually, because we don't anticipate anyone actually using our open source reference implementation in production, we hope that CPU vendors will take the ISA extensions and apply them to their own chips, but we expect that (if they do) they'll do independent reimplementations. At the ISA levels, we have PVS / SAL proofs that we'll be publishing soon that the ISA does provide the desired security properties and you're welcome to audit those too.
THE goal of PowerPC was not to make it easy to emulate 68K and x86. It wasn't even A goal.
You might want to go back and read some press releases from the AIM alliance at that time. Or even look at the ISA: there are a lot of things in there that only make sense if you want to emulate m68k or x86. They were positioning PowerPC as a migration path from m68k and i386 systems and being able to emulate both at a reasonable speed was part of this strategy.
grep me no patterns and I'll tell you no lines.