For both of the world wars, the United States mobilized by drastically increasing war production and output. It also used campaigns to rally everyone around the war effort.
The answer is actually d it was desti
The doctrine of popular sovereignty was used. That meant that people in those states could choose to vote to support slavery and since they were majority then slavery would be permitted. There were even states that were at first non-slave states but then things changed and they voted to introduce slavery into the state and people voted for this and supported this.
