In his new book The Perfect Kill: 21 Rules for Assassins, former CIA case officer Robert Baer uses Mughniyeh’s career and tactics as a case study of the dos and don’ts of political assassination.

Speaking to CNN's Jake Tapper on Tuesday, Bob Baer, who worked at a CIA case officer primarily in the Middle East, said the US has purposely muted its response to journalist Jamal Khashoggi's murder.