Answer:
The impact of the United States joining the war was significant. The additional firepower, resources, and soldiers of the U.S. helped to tip the balance of the war in favor of the Allies. When war broke out in 1914, the United States had a policy of neutrality.
Explanation:
I think that's right
Abraham Lincoln was most popular in the Northern states. The states he won were anti-slavery. The candidate who won the electoral votes in the south was Jefferson Davis.