Just a quick shout-out in support of 'societal' from an academic social science and political philosophy perspective, as suggested by some posters above. In this field, 'societal' is frequently a useful word when wanting to distinguish different levels/units of analysis. That is, 'societal' would be used to indicate that one is speaking at the level of societies taken as wholes, whereas 'social' tends to suggest goings-on internal to societies. For instance, "Habermas's approach is to offer a general theory of right conduct, concerned with the social interactions of individuals and groups, whereas Rawls's focus is purely at the societal level, concerned with what he calls the 'basic structure' of societies; their dominant institutions, laws, schemes of distribution, and so on."

In other words, 'social' = pertaining to things that happen in societies; 'societal' = pertaining to societies as entities. Definitely not just trying to sound clever or complex or newfangled, which I dislike as much as the next language connoisseur! (Looking at you, 'disconnect' as a noun.) It's just that precision of meaning trumps all else in my book.