Some assert it's inalienable.

(I don't agree - re-read my wording carefully - but some certainly take that position. My point: those who do still tend to take the "but there are limits!" position on, say, home-brewed nukes.)

In each case, though - constitutional right, human right, inalienable right, natural right - the fundamental concept of "sometimes two people have rights that conflict, and society has to resolve this" applies.