A good article, but I suspect Twitter and Facebook for the most part reinforce existing narratives. For example, IDF posts near real time they have become operations in Gaza against terrorist targets. Those who identify Hamas as terrorists will accept this because it reinforces their narrative, and they may appreciate the timely update. Those who support Hamas, or associate Hamas with the larger Palestinian issue, will interpret this as Israeli aggression regardless of Israel beating Hamas by a couple of minutes in getting their Twitter post out first.

Over time I think select u-tube videos that go viral showing civilian casualties on both sides can erode support for either side, and conversely increase support for the other, but there must be more to it than speed?

David, SM can have an impact in remote areas indirectly just as missionaries and others have an impact in remote areas. Those who travel to these remote areas carry the messages from SM with them, so while the connected world interacts real time exchanging information (or disinformation) via social media, those in remote areas that may not be connected will eventually hear it if they're a population that people desire to influence. If they're not then it is largely irrelevant.