It is worth noting that the people who knew LHO believed that he did it. Michael Paine was no exception. I find it interesting that Michael said he was given a chance to see LHO by the DPD and he declined.
Yes, but not the people who knew him in the Soviet Union. Mailer interviewed many of them for his book - and they've been interviewed elsewhere - and to a person they all said they couldn't believe it. The Oswald they knew, they said, couldn't have assassinated JFK.
I think that's not just them succumbing to Soviet propaganda. Priscilla McMillan made this point in her review of the Savodnik book "The Interloper." Savodnik said the angry violent Oswald could be seen in Minsk, there was a straight line from there to Dallas; McMillan said no, it was a different person.
McMillan: "Savodnik goes so far as to say that if the reader understands Oswald’s life in Minsk, he or she will understand much about how the Kennedy assassination came about. This claim is a stretch: the anger and violence that were to characterize Oswald’s behavior after his return to the United States were barely visible during his time in Minsk."
Oswald really did become erratic and unstable in the US; much different person then he was in Minsk. I think in particular after being turned down by the Cubans he realized he had no where else to go; this was it. And "it",
who which I think he blamed the US government for (especially the FBI), was something he could no longer live with.