

It makes sense in war, since people need normalcy. Partaking in Ramadan is a nice grounding thing to do when everything else is exploding, and other normal traditions aren’t on the table. Religion is good for that.
Plus, Ramadan traditionally has exclusions if you’re not able to safely partake, like if you’re very old, very young, or ill. At worst, you simply have to pray for forgiveness for breaking your fast early (similar to if someone made you eat pork without your consent).
Not if you’re in a place that relies on satellite infrastructure, such as places conventional telephony doesn’t work in.