What is going on historically in the 1950s-1970s that creates so much social upheaval in america?

During 950-70, the racial discrimination was fought. Courts ordered desegregation of schools. The expansion of civil rights movement occurred in 1960. Social mobility and comfort were observed post-war. in 1964, President Johnson enacted the Civil rights act, in the memory of Kennedy. 
All of these events upheaved social prosperity and equality in America.