If this topic is of any interest to anyone else, below is the first page of Cone's preface to "A Black Theology of LIberation", 1970 Edition
"The reader is entitled to know what to expect in this book. It is my contention that Christiantiy is essentially a religion of liberation.
I need go no further than the "religion of liberation."
This tells me Cone has religion and social justice mixed up in his head.
Nothing could be further from the truth, i.e. "Christianity is the redemption and salvation of souls."