After revealing the existence and cancellation of Fallout Extreme yesterday, The Vault brings us further details about the preliminary gameplay ideas that were being kicked around at Interplay back in 2000.
The game was not going to be just a shooter, but rather "a game of action,tactics and strategies where moving into position, planning and falling back" is just as essential as having the biggest guns around. The world map was divided into territories, each of which had different layouts, population of various enemies, different geographical strategic significance etc. Strategy would come into play based not only on the tactics employed for a given mission, as the dynamics of each mission would be different based on whether the player entered the territory from the west, south, north, etc. To get to a particular territory, one could e.g. choose either to charge through an enemy stronghold or to sneak around through adjacent territories in order to flank the enemy.
Missions would also be interconnected and your choices would have consequences. E.g. if the player destroyed a bridge in the territory of one mission, the enemy forces might be weakened in the next one, because of lack of reinforcements. Conquering and holding territories with productive towns would be essential for establishing and maintaining supply lines. If there were a supplied camp nearby, the player's access to various kinds of weapons, ammo etc. would be constant and reliable. The player could close off a territory, forcing enemy troops to pass through another territory, where an ambush could be set up. It's actually a shame that Fallout Tactics did not have stuff like this.