[Morthoron]

Rumil brings up several good points, and the more one considers Tolkien's battles (I am speaking of those in Lord of the Rings and the Hobbit), the more we find Tolkien eschewing direct combat sequences altogether for battles being recounted after the fact. At least two of the most important battles (to the plot, at least) are the Battle of Five Armies and the Battle before the Black Gates. In both cases, the battles are interrupted before they get heavy (in one, Bilbo is knocked unconscious, and the other Pippin is smothered beneath a troll). The actual battle scenes are described later under much more favorable circumstances.

And if anyone has spoken at length to any war vet (like my father, a WWII vet, for instance), they recall the glorious events or the fun times they had. You have to literally pry any reminiscences of horror out of them with a crowbar (if they'll reveal them at all). They don't want to talk about it unless they are forced to (and this is particularly true of WWI and WWII vets for some reason). Tolkien's reminiscences of horror (like the faces in the Dead Marsh) are subtle reminders of his personal war experiences, rather than the overt statements made by Owen, Sassoon or Erich Maria Remarque.

Tolkien's books are epics presented in a classical, nearly mythological form (the Sil more so than LotR, but nevertheless legendary elements literally appear on every page); therefore, the plot centers on the noble heroes (even Samwise the Everyman is Jack in the Beanstalk, for all intents and purposes), and the crises and eucatastophe are fairy tale in quality (a quest, a ring, the destruction of an immortal evil, etc.). Tolkien was strident, almost vehement, that LotR was not allegorical to WWI or WWII, and for good reason. It has nothing to do with real world conflicts; rather, it has everything to do with Faery and a rousing tale on the grand scale.