So these nations are at war, but the ground troops aren't invading in foot? Instead, they're in barracks or never raised to begin with? What relevance could this have to the quote from Gattling?
Probably none at all.
Probably none at all.
So how might a global and region powers engage in a war without engaging in territorial invasion? What kind of advancement might allow such a conflict to take place with only a tiny number of combatants?