When the news covers the conflicts in the Middle East and North Africa, they often use the term 'asymmetric war.' It sounds smart, but what does it mean? Let's start with 'symmetric war,' which is your classic open war between enemies with roughly the same resources, equipment and strategy. For instance, in World War 2, both the Axis and the Allies had ships, airplanes, tanks and troops.
In an asymmetric war, the two sides may be unbalanced, at least on paper. In Afghanistan, ISAF (International Security Assistance Force) has satellites, air power, armor, artillery and well organized infantry. The Taliban have no planes, few vehicles, and fight in irregular groups using improvised bombs.
This brings in the second definition of asymmetric war--it can be a war where the enemies use very different strategies and tactics. I don't think these two definitions are really separate, because what tools you have and where you're fighting often dictate your strategy.
While some analysts label this 4GW (fourth generation warfare), guerrilla tactics and insurgency are very old. The interesting part is how the better armed powers of the West are responding.
It's easy for us to picture military history in a simple way, with massive, colorful Napoleonic armies slamming into each other on a field somewhere in Belgium. Or Union and Confederate troops slugging it out in an orchard. But when we think of Jihadist groups like al Qaeda or Boko Haram, we imagine them as hard-to-locate terrorists slinking through a city at night, planting bombs.
But the truth is that during all wars, just finding your enemy can be difficult. Even large armies can miss each other. Two ways to learn about your enemy are scouts and spies. Scouts find your enemy and protect your own force from surprise attacks. Spies tell you about your enemy.
In the current wars, the Western countries face enemies who go beyond guerrilla tactics and into political and religious terrorism. The West has great technology and well-trained militaries, but often doesn't know who an enemy is until after they strike. Identifying our foes is where spy work is key.
Terrorist groups enjoy many advantages, including endless targets because they are eager to kill civilians. They hide among the very population they intend to kill. But they are still vulnerable to scouts and spies.
Ever wonder about the drone strikes in the news? A US drone fires a missile into a car load of terrorists on a remote road somewhere. How did we know who was in the car, or that they were terrorists, or which road they would take?
On the opposite end, you have the Taliban in the mountains of Afghanistan, who are able to ambush ISAF forces and then disappear. They may be poorly equipped, but they are apparently very good at scouting.
Whether it's a spy satellite high overhead, or an agent with a cell phone, or a special forces soldier with binoculars, scouts and spies do the difficult work of identifying and locating enemies. Somehow militaries drift away from this concept, and it seems we have to relearn it every time a new war begins.
The technology has changed, but the principles have not. I think every war is asymmetric.
(This Asymmetric Warfare page has a bunch of papers, but I didn't see anything more recent than 2007. I found this article particularly interesting, "On Boyd, Bin Laden, and Fourth Generation Warfare as String Theory" by Col. Dr. Frans Osinga.)