Organized marauders, a serious thorn in the back of regular armies

[simonmark6]

The Rhodesians did exactly this with aircraft. Each isolated farm was expected to be able to hold out for a certain amount of time during which a Rapid Reaction Force would fly in and try to catch the guerrillas so it has worked relatively well in modern times.

Depending on the terrain you are defending you can add a trip line of outposts on the border of your territory in order to give the Reaction Force a head start. Of course, such tactics can be used against you, as all can. If I was a marauder unit with enough resources I'd launch a diversionary attack on a fortified hamlet specifically to ambush the Rapid Reaction Force which would be a good source of equipment and high value hostages. If you got really lucky you might even defeat the occupying forces so thoroughly that you'd have a few weeks free rein rampaging around the land.