Having both Return to Castle Wolfenstein out and Medal of Honor: Allied Assault forces one to makes some personal decisions. The situaion also raises some deep philosophical questions as well.

“Do I kill Nazi Zombies or regular Nazis?”
And–
“Will it ever be politically incorrect to kill Nazis in a videogame?”

Or you could just play the damn games. Both are pretty fun. MoH:AA is a more realistic shooter, having its roots in the research done for Saving Private Ryan. Y’know, that World War II movie.