Donald Trump’s pick as the new CIA chief was a key figure in what a Republican elder statesman has labelled “one of the darkest chapters in American history”.

Within hours of the announcement of the appointment of CIA deputy director Gina Haspel to chief of the agency, Ms Haspel’s past involvement in the torture and waterboarding of al-Qaeda operatives in a secret Thai prison were dredged up and raked over.

“The torture of detainees in US custody during the last decade was one of the darkest chapters in American history. The Senate must do its job in scrutinising the record and involvement of Gina Haspel in this disgraceful program,” Senator John McCain thundered on Twitter.

Senator McCain, who was tortured in captivity in the Vietnam War, added that Ms Haspel needed to explain the “nature and extent” of her involvement in the CIA’s interrogation program as the Senate considered her nomination.

In 2002, Ms Haspel was sent by the CIA to oversee a secret prison in Thailand, codenamed “Cat’s Eye”, which handled the rendition, detention and interrogation of al-Qaeda operatives involved in the September 11 attacks on New York.

Her appointment this week as CIA director was triggered by Mr Trump’s sudden decision to fire Rex Tillerson as secretary of state and replace him with CIA chief Mike Pompeo.

Speaking to reporters soon after the news broke, Mr Trump said: “She is an outstanding person who also I have gotten to know very well.”

But Ms Haspel is expected to face a fiery Senate confirmation, in which she will be grilled by senators about her part in the waterboarding and torture of prisoners.

The New York Times predicted the CIA boss-designate will also likely be asked if she would reinstate waterboarding – which during the 2016 campaign Mr Trump promised to bring back – and her views on torture as a counterterrorism measure.

If the Senate does approve her appointment, Ms Haspel, 61, would become the first woman to head the agency.

‘Up to her eyeballs in torture’

After joining the CIA in 1985, Ms Haspel held several top positions, many of which were undercover roles, and until the Cat’s Eye controversy, she was considered one of the agency’s rising stars.

But the deputy director of the American Civil Liberties Union, Christopher Anders, branded her as the “central figure in one of the most illegal and shameful chapters in modern American history”.

“She was up to her eyeballs in torture, both in running a secret torture prison in Thailand and carrying out an order to cover up torture crimes by destroying videotapes,” Mr Anders said in a statement.

According to The New York Times, two September 11 suspects were waterboarded 266 times at the prison under her watch. One, Abu Zubaydah, was reportedly sleep deprived, kept in a coffin-like box, had his head slammed against a wall and ended up losing his left eye.

Abu Zubaydah. Photo: AP

Abu Zubaydah was ultimately found by the CIA to not have any useful intelligence.

Later, as the chief of staff to the head of the CIA’s Counterterrorism Center, Ms Haspel also drafted a 2005 cable ordering the destruction of dozens of the interrogation videotapes made at the Thai prison.

But Ms Haspel has also had support from many quarters. When she was appointed deputy director in 2017, former director of National Intelligence and Obama-appointee James Clapper called her a “seasoned veteran of the Agency who is widely and deeply respected by the workforce as well as those outside the Agency”.

George W Bush’s CIA director Michael Hayden described her as a “wonderful choice” and “a trusted friend, lieutenant and guide to the sometimes opaque corridors of American espionage”.

Who is Gina Haspel?