Every Fallout game has begun with Ron Perlman explaining to us that "War Never Changes."
But somewhere along the line you'll find yourself fighting household appliance robots and scorpions the size of a Buick in a post-apocalyptic wasteland using your nuclear-powered plasma rifle and realize that you could make a pretty good case for this being different from the wars of the past.
If you're really looking for something that doesn't change, I might suggest dismembering a few super-mutants with the ripper. That never gets old.
I'm going to go do more of that right now.
Shamus Young is a programmer and writer by trade, videogame nitpicker by inclination. If you have the patience for more of his ramblings, they can be found at ShamusYoung.com.