And it was purposeful with malice aforethought. It was all part of the big leftist push to transform our society, and then our government, into a collective with little value for the individual.
First, the society must be divided into opposing groups. Feminism divides men and women; "civil rights" and affirmative action divides the races; welfare and high taxes divide rich and poor; unions divide management and labor; the gay agenda divides us along sexual orientation lines.
That makes it convenient for the left to take the side of the "oppressed" groups they created. With enough oppressed groups political power is assured.
There is more but that is enough for now.
Bingo! And you summarized it very well, I might add.