Megan Garber takes on Instagram Direct¹ in Behold, Facetwitterest: The Standardized Future of Social, and makes this observation:

So one of the biggest challenges facing the major (and the trying-to-be-major) social networks is a structural one: How do you build yourself up and out in ways that balance users’ desire for intimacy with their desire for publicity? How do you merge the web’s ability to create communities with its ability to create universalities? 

You could read Direct as Instagram’s (and Facebook’s) latest attempt to navigate that tension. The service is, basically, attempting to add a layer of privacy to its existing, public-leaning architecture. But Instagram isn’t just Snapchatting itself. It’s offering its users a Snapchat-like functionality within the context of its much more public social network. It’s trying to have it both ways — cynically, but perhaps ingeniously — by offering a refuge of privateness within a very public service.

It reminds me of something Luke Wroblewski said recently:

Every mobile app attempts to expand until it includes chat. Those applications which do not are replaced by ones which can.

Direct appears to be a necessary defensive move by Instagram — private messaging is now a basic expectation for social networks. But it also looks like people are getting more savvy about their privacy and what happens to their data (Thanks, NSA!), so it will be interesting to see how this mixing of public and private plays out in 2014.