You should write about how protection would be your main concern, how you would employ all-hours guards to patrol the boarders of the town or city, you would make sure by a certain time of day, everyone was in their homes, safe and sound, and make sure there are refugees built underground or in shelters for protection. You would supply the people with supplies in case of sudden attack. The town's chief threats would be potential poisonous gases or nuclear weapons used against them, quick, random attacks from the opposing group, and potential poisoning or destroying of water, or food supply. Hope this helped!!