Because the us did not want to be together if some states did not agree with the others so they craeted two sides that divide the us
Answer:
A. The election of Barack Obama
Explanation:
Post racial era refers to the United States being free from racial discrimination, segregation and preference.
Barack Obama was elected President of the United State in 2008 and was regarded as the first black president of the county. This made people to conclude that the United States has truly reached its post racial era.
