Certain circumstances, such as strong religious beliefs or a totalitarian system of government, can "inspire" citizens or factions to nationalism that approaches maniacal fervor. Fanatical groups can often succeed in seemingly hopeless situations, fighting and defeating superior enemy forces. Often, fanatics pursue military and terrorist activity for years, even decades, before they can be caught or stopped. Their strength for both attack and defense comes from their willingness to fight for the ideals they believe in, and, if necessary, sacrifice their lives in the name of their cause.

Partisans -
Partisans are militant groups who pledge their support to a leader or a system of government. Partisans differ from fanatics in their methods. Whereas fanatics are usually radicals prone to use terrorist tactics, partisans are usually trained soldiers who practice the more organized tactics of guerrilla warfare. Partisan groups have existed at various times throughout history. Partisans were particularly active in the Nazi occupied countries of Europe during World War II, where their acts of sabotage against their conquerors often kept German troops busy quelling partisan uprisings while they should have been fighting on the front lines. Because of their unflagging dedication to their cause, partisans make formidable opponents.

I feel if you build (or assign a pop unit) to be Partisans or Fanatics, they should be independant units that can do as they please, and should they attack an enemy civ that you are not at war with, it will not cause the nation to declare war on you. It would be labeled a terrorist act. This way, after a city is captured, the partisans that "jump out" are not under your control, but if they take the city back, the city is under your control again. If you sign a cease fire though, (In Civ 2) the units must disband or go to the nearest city. This isn't right, the Partisans, cease fire or not, will attack the city to recapture their land! But this shouldn't affect your cease-fire if they fight to get the city back. if not, I would like to see a "terrorist" unit or ability for Fundamentalist governments in order to attack without having diplomatic consequences.

Whether in Civ3 you would have any cargo to steal remains to be seen, because the trade system is going to be overhauled. Even if this is not to be, I still think there is a case to be made for including a Pirate ship unit of some kind. Apart from perhap's the modern age, they appear in one form or the other all through history.

And the privateer principle would apply really well to partisans because governments often covertly fund groups in other countries. In civ3 this could be represented by you building a unit (eg partisan), and being able to control it inside your borders, but as soon as it leaves your borders, it becomes semi-independent.

But I was also thinking that privateers could severly unbalance the game if they're left to roam free, so how about them requiring progressively more shields to support the further they are away from the nearest friendly town?