On Facebook, Jacqueline Lichtenberg asked a question about why Chuck made certain decisions regarding communications with the front line during a battle sequence. The response is interesting because it gives insight into the level of detail of thought needed when writing a battle scene. Why does it work the way it does? (Taken directly from Facebook)
JL: A question: when communications are all out in the Jakarta region and they have to instruct troops about the action, why don't they send out loudspeaker trucks and guys with bullhorns? Is this so far in the future nobody has such things or are they all destroyed? Or did I miss something?
CG: Lots of reasons. In no particular order: (and I speak of trucks, but same would apply to runners with bull horns)
1) Counter targeting invite. Audial triangulation would find snipers easily by this time; Speaker trucks would be like "shoot me" signs.
2) Difficulty with centralized control relaying to trucks. Control net by subsurface fiber optic, in absence of any ability to use airwaves, or to trust that you could safely signal in the clear, means you have to go for secure hardwire/fiberwire.; Trucks would have to get messages, return for more. Turnaround time fatal for contemporary MOUT [Military Operations on Urban Terrain] scenario depicted.
3) Centralizaiton trackback of source of truck messaging: a half witted adversary will realize the trucks are having to get updated with messages. Find, observe, follow messenger or truck path to update point, and you take out a commo nexus. Given difficulty of insurgent C4i environment, it is probably a command and control nexus. High value target; crippling blow to insurgents.
4) Trucks not historically used in front line engagements as passing info; usually preop marshalling, often for civilians, not troops. Useful for issuing mass directives to masses. The more closely orchestrated or tightly sequential an operation is, the more its communications must be inaccessible to the threat force, swift, clear, coded. None of that is possible with speaker trucks.
There are more reasons (having to do with logistics, inability to get immediate ping backs to determine yes/no on receipt of message and therefore op timing confirmation, etc.) But you get the picture.