Firn:

According to this definition all armed forces swarm.
Yes. Yes they do.

Quote Originally Posted by William F. Owen View Post
I keep hearing about Swarming, but no one actually seems to know what it is. If it just means simultaneous attacks from multiple directions, then its hardly a useful characterisation.
Actually, that's precisely what it is.

To quote Sean J. A. Edwards in his work on the topic, swarming is:
a primary maneuver that results in an attack from multiple directions (all points on the compass) by 5 or more (semi) autonomous units on a single target/unit.
Not sure why defining and understanding the past, present, and future of a core component of warfare isn't useful.

Moving on, here's what Ronfeldt and Arquilla wrote in 2000:

Examples of swarming can be found throughout history, but it is only now able to emerge as a doctrine in its own right. That is largely because swarming depends on a devolution of power to small units and a capacity to interconnect those units that has only recently become feasible, due to the information revolution.
Which is very much in tune with what Marc wrote:

Smaller units and increased segmentation can work and be incredibly effective, but they are dependent upon the technologies involved, especially the defensive, mobility and logistics technologies, and the use to which they are put.
Arquilla's basic point is that the world has changed - we've entered an era of unprecedented connectivity and, logically, military structure should reflect that shift.

Swarming is a useful approach to understanding how to do so, and the rules Arquilla outlines are useful in thinking how to accomplish that task - smaller units (#1) wielding sophisticated information flows (#2) are able to accomplish complex and varied tasks as the need arises(#3).