I first saw the idea of swarming in a science fiction story by Larry Niven. I hope to find someone who can tell me which book this is in. Niven had several instantaneous travel methods that showed up in stories, this one incorporated the use of booths - a user would step in, dial up the destination booth, and step out at his destination immedately. Obviously there is a big difference between cell phones and "transfer booths" but the idea of swarming - especially to express opinions of the leaderless - is an exciting prospect from an old victim of the "silent majority" based government.
I bring this up for two reasons. The Post story credited the military while everyone should know that science fiction authors are the most likely suspects for beating the crowd to an idea. The other reason is that Niven's story had a system-wide fix instituted to stop crowds from jamming to a location and overwhelming the police. I would like to re-read the story to see if he was predicting something that has come to pass as well as to see if his "fix" has any application that officialdom might try to use to establish control over the freedom to swarm.