He was a psychological profiler for the CIA, examining the minds of world leaders such as Saddam Hussein and Kim Jong-il.
But in his later years turned his attention closer to home, penning a book on the mindset of US President Donald Trump.
Jerrold Post, a former political psychologist and author, died from complications related to coronavirus in late November at the age of 86.
Those who knew him have paid tribute to his work.
Magnus Ranstorp, a special advisor to the EU Radicalisation Awareness Network, described Post as “very gentle, kind and with a sharp mind”.
Jessica Case, a publisher with Pegasus Book who worked with him on his last book on President Trump, told the BBC: “His knowledge and insight into psychology were unmatched. He was endlessly curious.”
Analysing the minds of world leaders
Post, born in 1934 in New Haven, attended Yale University, where he did his undergraduate degree, before heading to medical school.
He then undertook his postgraduate psychiatric training at Harvard Medical School and the National Institute of Mental Health, according to the Washington Post.
Post spent more than 20 years working at the CIA. He set up the agency’s Centre for the Analysis of Personality and Political Behaviour in the early 1970s.
“We looked at foreign leaders in their cultural and political context and gauged to what degree they were playing out personal conflicts on an international stage,” he told Yale University.
The unit analysed foreign leaders such as Cuba’s Fidel Castro, Iraq’s Saddam Hussein and Libya’s Muammar al-Gaddafi. Their assessments enabled presidents and high-profile officials to prepare for negotiations and crisis situations.
Post wrote the “Camp David Profiles” of Egyptian President Anwar Sadat and Israeli Prime Minister Menachem Begin, which were said to have significantly influenced President Jimmy Carter’s strategy for negotiations at Camp David – the US presidential retreat in Maryland – in 1978. The ensuing accords, signed by the two leaders, led directly to the 1979 Egypt-Israel Peace Treaty.
In his book Keeping Faith, Post said: “After Camp David, there was scarcely a major summit without our being asked to prepare profiles and assessments of the foreign leaders.”
Post was awarded the Intelligence Medal of Merit in 1979.
He then went on to assume his position of director of the political-psychology programme at George Washington University’s Elliott School of International Affairs.
However, US government officials later called on Post again to help guide them in their decisions surrounding Iraq and Saddam Hussein.
Speaking to the BBC in 2002, Post said Hussein had a “traumatic upbringing”. Hussein fled his parent’s home, who refused to give him and education, and went to live with his uncle who “filled him with these dreams of glory”.
Post said this cultivation of grandiose fantasy turned him into a “malignant narcissist”.
Analysing the US president
Post wrote 14 books on a range of topics, from the mind of terrorists and the increase of politicians with narcissistic personalities.
He faced some criticism during his career for diverging from the American Psychiatric Association’s (APA) Goldwater Rule, which prohibits psychiatrists from commenting on the mental health of public figures, or diagnosing them, without examination and consent.
However, Post argued that it was sometimes unethical to stay quiet.
“I think there’s a duty to warn,” Post told The New Yorker in 2017. “Serious questions have been raised about the temperament and suitability of He-Who-Must-Not-Be-Named,” he said about President Trump.
In 2019, he took this idea further, co-writing a book with Stephanie Doucette titled: “Dangerous Charisma: The Political Psychology of Donald Trump and His Followers”.
In a interview with news site Salon ahead of the release of the book, he predicted Mr Trump’s moves following the 2020 election.
“Should Trump win, as he did in 2016, he will make it a much bigger win and talking [sic] about the fraudulent election support on the Democratic side. But should Trump lose narrowly, I think we can be assured that he will not concede early.
“Trump may not even recognise the legitimacy of the election,” he said.
Following the book’s publication, Post’s health began to decline and he suffered a stroke in July.
He spent his final weeks at home and died on 22 November, a week after testing positive for coronavirus.