This is how I see it...
The problem is that we use the words terrorist and insurgent and guerilla interchangeably. They are not interchangeable words.
Terrorism is meant to sow fear, disorder and discord (by virtue of bombs, traps, ambushes, etc...) amongst a civilian population in order to effect a specific shift in popular public opinion. Directed at civilians.
Guerilla warfare is non-conventional warfare, conducted by uniformed or non-uniformed persons against a military force, intended to create an untenable atmosphere for continued military involvement...raising the 'blood price' on an enemy military. Directed at military personnel.
Insurgency is guerilla warfare conducted by parties outside the conflict who choose to 'immigrate' into a region and conduct guerilla actions.
Our nightly talking heads fail to recognize the difference, and fail to realize that the current affairs in the Middle East are, in fact, a combination of all three, depending on the scenario.
For example...a roadside IED, detonated for a military target, is an guerilla/insurgent action...not terrorism.
The same IED, detonated for a civilian target ( a car full of She-ites {damned filter again}, blown up by Sunnis) is terrorism.
A hit-and-run ambush on a military convoy by irregulars is guerilla tactics. A car bomb in a marketplace is terrorism.
So, no...the French Resistance was not a terrorist organization, as it's actions and purpose were specifically oriented around the German military. To my knowledge, the FR also conducted actions against collaborators on an individual basis...not by blowing up schools to make a point.
Terrorists kidnap, maim, torture and behead civilians...it's not 'irregular war'...it's terror for terror's sake.
Lastly, I would contend that all of these comparison are actually extremely difficult to make for one very simple reason: Another time and place.
We have to remember that social values and mores were significantly different back then, and not subject to exactly the same perspective as today's nannified societies. At that time, for example, waging war against civilian populations was par for the course. Routine. Thousands upon thousands killed every day in city bombing, firestorms, dams down, etc...
Today, if a US soldier farts in a diner it's a war crime.
Of course...this is all just opinion.