The ‘Tears of Autumn’ is fiction but makes an intresting case since almot national governments and former heads of state do have professional hit teams in the rolodexes. Certainly Madame Nhu did and the possible of her husband’s murder by American plotting had been discussed by that tough couple. Madame Nhu particularly hated Jackie Kennedy and made no bones of her pleasure over JFK’s murder and Jackie’s distress. (But there were some Americans such as my mother who felt the same way. To my granite hard momma, JFK and Co. had isulted the gods with their hubris and paid the price.)
There’s no doubt that Madame Nhu was a tough cookie. That theory makes more sense than any other one that I’ve ever heard. Personally I think Warren got it right but the Nhu theory is intriguing.