The effort to protect society in the event of a military attacks is civil

Probably, you want me to supply the missing word.

civil defense

Explanation:

"Civil defense" is considered an effort to protect the citizens in a society in cases where natural disasters and military attacks occur. This was primarily focused against the military attacks during the Civil War, however the focus shifted to natural disasters and other related emergencies after the Civil War.

Civil defense includes the organization and management of resources in order to meet the different aspects of the emergent situation.

So, this explains the answer.

england is crowded cold and polluted while north america was like the opposite