What exactly is a war in heaven, and how many casualties in heaven did it create. Where is the sense of it because normally during a great battle preperations are made for injured combatants. Was it a deathless battle , or because it was spiritual was it bloodless? Were there advanced field dressing stations, or Generals or courts marshal? There are so many unanswered questions that it seems just a tad too far fetched for my mind to figure. What would the Devil's or God's main weapons be? couldn't be machine guns beacuse the bullets would go straight through,couldn't be explosive devices or there would be bits of angels everywhere. Could it have been psycological warfare ,but then both sides must have used it for it to have been a battle. You can't have a battle if one side has no weapons of destruction. Did both sides believe they had right on their side ? It cannot have been much of a battle if God had had all the weaponry,a bit one sided that. Were there atrocities committed on both sides? Do we need an enquiry?
Conclusion ; It is a figment of someone's imagination, so do not believe everything you read,especially if it's in the Watchtower.