The war fighting functions

FM 3-0 lists six War Fighting Functions.

Movement & Maneuver
Command and Control
Sustainment
Protection
Intelligence
Fires

Each "War Fighting Function" is a measure of how robust a particular combatant is in a particular area.  When you combine the War Fighting Functions with "Leadership and Information" they become the "Elements of Combat Power."

Let us take a look at the Taliban.  They have minimal movement and maneuver, minimal command and control above the platoon level, minimal sustainment assets, minimal protection assets, extensive Intelligence support, and a few rockets and mortar tubes for indirect fires.  They don't have a lot, but they use what they have to stay in the fight.

On the flip side, when you examine the other sides War Fighting Functions you can identify weakness that can be exploited.  If the enemy has a really good "Movement and Maneuver" asset like a motorized brigade, but a weak "Sustainment" support network, simply by blowing up a few dozen fueling trucks you can greatly reduce the "Movement and Maneuver" advantage.

However the enemy is doing the same to you.  If you are the underdog you will not have an advantage in any of the War Fighting Functions.  Any "American Insurgents" need to take note.  However, there are ways to stay in the fight when you are the underdog. 

Having a cell structure means that the enemy has a hard time attacking your Command and Control assets. 
Living with the locals and maintaining support from the population means that the .gov would have to target civilians to cut off your supply line.
If all your movement and maneuver is through civil means, the .gov must crack down on everyone to crack down on you.  (I think that is why the TSA is so heavy handed, to get people used to being treated as war criminals or terrorist suspects.)
If you don't have a large base to protect your forces at night the .gov can't attack what isn't there.  (hence the need for anonymity, once big bro knows where you are the game is over.)
If you don't have mortars or artillery it only means you have to resort to IEDs or heavy direct fire attacks (rpg or rocket).
And intelligence, this is the only thing keeping the Taliban in the fight.  Their ability to recruit fresh meat.  Intelligence isn't just about gathering information on the enemy, it encompasses all intelligence operations.  Including recruitment.

Don't get me wrong, the Taliban gets its ass handed to it on a daily basis.  The VC got severely spanked in Vietnam.  But the propaganda would tell you that the Taliban are filled with spartan mujahadeen fighters who live solely to fight and die for Allah.  It isn't the case.  Your average Taliban fighter is a near sighted, underfed, brainwashed guy who thinks of going on Jihad as a temporary thing to gain some street cred.

We could do the same for the American Revolutionary War and see how the American weaknesses in Sustainment were made up by Movement and Maneuver (Washington lost more battles than he won, but he stayed in the fight), how Washington used Intelligence to augment his Maneuver assets (both tactically and strategically), and how Command and Control worked to unify lines of effort across the Eastern Seaboard.

But the Six War Fighting Functions don't tell you who will win.  They only tell you who is more robust at a particular area of war.  Every war has always had a difference in forces.  Someone always has more than the other guy.  A smart guy looks for how he can undermine the enemy War Fighting Functions.  Feed them false intelligence?  Deny them mobility with road spikes?  Use an EMP bomb to degrade their C2 assets?

You can analyze War Fighting Functions all the way down to the individual if you wanted to, but it is most useful when looking at a group that will be fighting together for a while, Squad or Platoon sized generally.