Information on levels of restraint is needed.

So, as some of you may know (if you've read the last blog regarding story ideas) i will be making stories that center around death, and war. Now what i want to know, is how far i should go with that, where do i draw the line?
To put it simply i'm putting elements from Call of Duty, Battlefield, and various other titles, now that brings up some major issues, do i go Modern Warfare levels of all in? Do i really wanna push it, and put in stuff from World At War? Do i nuke a city, or not? Do i put in the after shocks of warfare? These are tough questions to answer because i want to have a decent story line, and i haven't experienced war myself so i'm at a loss for how far and gritty i wanna get.
Perhaps i can get some help?