[magicalist]

> If nothing else, Mozilla does not have nearly as much money as Google, and really cannot afford a "tear down everything and rebuild it" approach like PNaCl

The rest of your post is spot-on, but this part isn't really true. The barriers to "tear down everything and rebuild it" are much more systemic and less monetary (just look at the small JS engine teams that got us where we are today).

Meanwhile, Mozilla Research certainly continues to grow, and Rust is a perfect example of a "tear down everything and rebuild it" project now run by them, albeit in a different domain than JS.

[BrendanEich]

The domain differs for Rust from JS or PNaCl. The latter are on the web. Rust is AOT compiled and for systems programming. It's competing with C++, not JS -- and not for safe C++ on the Web (not yet, anyway; Rust2JS and Rust on the GPU are of course on radars due to LLVM and eholk & co. at IU, respectively).

Even with Rust, we don't tear down Unix or DWARF, to pick two examples -- we use 'em for maximum leverage.