For those of you that don't know, the hero is tasked with saving his people in both Fallout 1 and 2, in one case a vault and the other a tribal village. After trudging out into the wastes and hazarding all its horrid threats, he returns home victorious only to find that the ugly world is not finished with him. In Fallout 1, his people see the scars he acquired while in their service and cannot risk the integrity of the vault by readmitting him. The vault banishes the hero to become a wanderer in the wastes. In Fallout 2, the hero's home is razed through the course of the narative, leaving him a vagabond.
The allegory at work in these games is that War (the world outside the security of the Vault/Village) forever changes the people that participate in it -- and not in a good way. It makes you do things that you would never wish to do or it does things to you which you wish would have never happened. You can attempt to keep your moral compass whilst dealing with war, but it will be impossible for you to come out of it unscathed.
Now, Fallout 3 and New Vegas subject the hero to these affects since War Never Changes, but they take away the most important part of the allegory -- living with it!
I miss the hazy fadeout of a cursed hero hunched under a great invisible weight soldiering on into an unknown future. That is the punishment of the wasteland. That is a world torn apart by humanity and a humanity struggling to live with itself. That is Fallout.
--antimike
