During the civil rights era of the 1960s, there were a great many different African American activists who made it to the mainstream forefront. A stark chasm at least seemed to initially exist between Malcolm X and the Nation of Islam and Dr. Martin Luther King. One was urban, hostile and embracing a religion that certainly is not alien to blacks in America or elsewhere but was fairly alien to midcentury America. The other, in King's movement, was rural, Christian and challenging the broader culture, not overtly hostile to it.
In to this plays a Marxist observation - the alienation of capitalism. Spike Lee's movie about Malcolm X is essentially the story of alienation. Malcolm, after losing his father to the Ku Klux Klan, spends his youth selling drugs and sleeping with a white woman, then eventually serving prison time, knowing full well what's problematic to him about each of these situations. When he finds the Nation of Islam, the community that he finds there is a diaspora for him within a largely uncaring urban environment. The Nation becomes hostile and, like all nationalist movements, may genuinely provide some relief to its adherents while only bringing hate toward anyone outside of it. Nevertheless, it provides something Malcolm couldn't find anywhere else, causing him both to cling to it and to feel intimately betrayed when the falling out occurs.
Martin Luther King, on the other hand, came from a rural environment in which oppression was certainly hot but enough space and air had been given so that African Americans were able to develop their own civil society, able to birth a man as full of empathy and warmth as Dr. King. King saw the danger in identity politics (that phrase not yet being in vogue) and spoke out against white nationalism and black nationalism and speaking of "the better angels of our nature" while the Nation spoke of "white devils." Both Malcolm, who was originally born in Nebraska (where his father was killed), and King came from similar rural backgrounds originally - the contrast occurred in the answers they found for similarly awful circumstances.
The divorce in approach of both King and the Nation of Islam (products of the less developed southern United States and the hyper-developed American inner city, respectively) reflected, in many ways, the sharp contrast between the third wordlist movements of Venezuela, Ecuador and Bolivia in contrast with the erratic and self-interested nationalist movements that seem to be having a rebirth in the developed world.
Certainly not free of problems and with less material wealth, the "third world" (a patently racist term of its own) nonetheless has social infrastructure where the developed world has depleted theirs. While first world religious leaders fan hatred and even its supposedly progressive leaders cheer on endless wars abroad, the third world regularly produces Mother Theresas, Oscar Romeros and Pope Francises. Capitalism alienates us more as it becomes more developed - only where it is undeveloped does humanity still reside. King himself got the chasm that exists - his speech explaining his opposition to the Vietnam war, at the time straining a possible relationship with Lyndon Johnson, is amongst his best work.
Liberation theology became a thing only shortly after Dr. King was assassinated. While it's not mentioned that much, I am sure that Gustavo Gutierrez was inspired by King on some level, even minute. The beautiful displays of interfaith spirituality that Pope Francis regularly engages in greatly reflect the arm in arm marches that King performed with pastors and rabbis of deferring denominations.
Liberation theology took off in the black community at least on a small level with the like of Cornel West. In our challenging times, perhaps it will be greater embraced.