It can still be expressed, of course. It's just that it wasn't particularly a reply to its parent and took the discussion on a generic tangent (U.S. = world police) that is also a classic flamewar topic. We don't kill such subthreads, but we do move them.

I can understand why you don't see it that way and wouldn't claim that our decisions are all obvious or all correct. They're imprecise judgment calls.