The dog that didn't bark: John Prados (link below) on the meetings discussing the coup.
"Records of the Kennedy national security meetings, both here and in our larger collection, show that
none of JFK's conversations about a coup in Saigon featured consideration of what might physically happen to Ngo Dinh Diem or Ngo Dinh Nhu. The audio record of the October 29th meeting which we cite below also reveals no discussion of this issue. That meeting, the last held at the White House to consider a coup before this actually took place, would have been the key moment for such a conversation. The conclusion of the Church Committee agrees that Washington gave no consideration to killing Diem. The weight of evidence therefore supports the view that President Kennedy did not conspire in the death of Diem. However, there is also the exceedingly strange transcript of Diem's final phone conversation with Ambassador Lodge on the afternoon of the coup, which carries the distinct impression that Diem is being abandoned by the U.S. Whether this represents Lodge's contribution, or JFK's wishes, is not apparent from the evidence available today."
The WH may not have actively wanted Diem and Nhu dead; but they - particularly Lodge (a truly bad guy in this awful matter) who was there on the ground - didn't do anything to prevent it.
On and on and on and on. All of these primary sources showing that JFK wasn't going to simply leave, that he was actively involved in supporting the coup, that he believed that a loss of the South would harm US security, all of this repeatedly ignored by the conspiracists, by those who think JFK was killed because he was going to withdraw. The evidence simply doesn't support that claim.
"JFK and the Diem Coup":
https://nsarchive2.gwu.edu/NSAEBB/NSAEBB101/