Answer and Explanation:
The text shows how it was necessary for a constitutional mandate to be created to ensure that the African American population was seen as American citizens and had access to basic rights such as freedom and life. This was the 14th amendment that was created long after the founding of the USA. The text shows that this amendment needed to be created, because the country was formed with a highly racist base, where the concepts of freedoms, rights and social duties were only promoted to the white population, and blacks did not have access to this, as they were considered unworthy, even in a country that has become independent in its quest for freedom and justice.
In other words, "Cornerstone of Civil Rights" shows that it was necessary for the equality and basic rights of the Afro-American population to become a federal law, in order to guarantee that blacks had a minimum quality of life, because the country devalued this population of very intensely at the time of its conception.
