Yes, I think I wasn't clear. What I was getting at was more about the mentality of programmers; if you can get stronger types into the mainstream you will also get many of the same concepts that you need to understand capability based systems into the mainstream. They aren't, strictly speaking, the same by any means, but right now the ideas in the area of provability, meaningful types, capabilities, and that whole complex of ideas around reifying not just what code does but what it doesn't do, just aren't popular enough yet. FP is the most likely vehicle to get that complex at least somewhat out into the mainstream. Once you have that, you might as well exploit it in your capability-based systems, even if they aren't strictly speaking related. Capabilities, on the other hand, don't look to me like they can lead the charge, but they could ride it.
I definitely agree with this. I also think that capability systems that are based on a good type system are probably going to be easier to code with than ones based on message passing security. The type systems make it easier to define and use the basic capabilities and involve a lot less boilerplate code than what one sees in other variants of capability-semantics.
