Has anyone considered the possibility that he was funded by the Israeli government? This would be one of the smartest ways to influence the US media, to finance a genuinely charismatic investor in media companies.
In Maxwell's case, he was working with too many different countries to be totally loyal to one in particular. He was semi-famous for publishing translations of awful hagiographies of communist dictators in the 80's (and of censoring other books as a favor to friends).