A Pew Research study found that in 2012 only 8 percent of adults use Twitter on a typical day. A good portion of those adults, though, are members of the media (nearly every member of the national press corp. uses the tool), passing brief comments and questions back and forth to one another about the day's news.
Has that screwed up the "national conversation" over the important issues?
Dan Mitchell, writing in Fortune, says yes, specifically in regards to the national security-personal freedom debate:
[T]he "national conversation" has for the most part been shallow, often bordering on stupid. That's because nearly everybody has retreated to their respective camps, refusing to recognize the validity of opposed arguments or the fact that this there is no easy solution to the problem of how we should go about strengthening our security while also, to the extent possible, protecting liberty and privacy. It's also because so much of the "conversation" has taken place on Twitter, where conversations, and certainly debates, should never take place, because they are engineered to be superficial. (Twitter's great for linking to stuff and for issuing pithy one-liners; it's absolutely useless for conversation.) In defending longstanding worldviews, rather than honestly addressing the issue, people are talking past each other.