D. The mobilization of entire populations for war efforts
Explanation;
A defining characteristic of total war during both world wars was that the mobilization of entire populations for war efforts.
A total war is a war in which the entire nation is involved in. However, there are many ways in which an entire nation can be involved in a war. The following social, economical, military and political characteristics of a society/conflict signify a total war/society that wages a total war.
The positive effects of getting California is that it's closer to Asia, and California side of the nation at the time could have open territory to conquer.
