In a mini-Twitter essay, Canadian Journalist Jeet Heer explores how the ideas of Heinlein and Hubbard influenced the rise of New Age beliefs and cults, even reaching into McNeil Island Penitentiary where a young, semi-literate Charles Manson would be shaped by conversations he would hear about Dianetics and Stranger in a Strange Land.
Keep in mind this is Twitter and none of the material is sourced but most of this information is pretty well established. The big takeaway here is that the "hard" science fiction of that era was very much about a mystical transformation of the human species using the language of speculative science. As Heer puts it:
L. Ron Hubbard was a con man, certainly, but not all of what he did with the development of Scientology was a put on. In the early days there was a giddy excitement where he and his followers truly believed they were uncovering secrets of the universe. What we think disparagingly of as cults today were often very sincere attempts to forge a new society which completely broke from the past and embraced a future that liberated mankind from the shackles of a suppressive society.
The irony is that any new social order, however seemingly progressive, will quickly harden into place with stiff rules and demand for conformity. The leaders will become corrupted by power and seek, not expanded freedoms, but control.
This is the curse of utopias. They are conceived of by flawed human minds and, in spite of their best intentions, will always be undermined by human nature.
Heer's entire storified essay can be found here.