Husain Haqqani, seen at right with Pakistani President Asif Ali Zardari in 2010, suggests at an inquiry on Tuesday that mutual mistrust made the envoy’s job untenable. (B.K.Bangash/AP)

Anyone who is asked to represent Pakistan in the United States faces a “tough and thankless assignment,” former ambassador Husain Haqqani told an inquiry here Tuesday, such is the gulf of mistrust between the two nations.

For Haqqani — who is caught up, as he sees it, in a serious deterioration in U.S.-Pakistani relations and a battle for supremacy between Pakistan’s civilian government and the country’s powerful army — that description is something of an understatement.

He was forced to step down as ambassador and return to Pakistan last month after being implicated in a controversy over a secret memo soliciting Washington’s help to prevent a possible military coup. For the former senior government official, author, journalist and scholar, it has been a stunning fall from grace, transporting him from the salons of Washington to virtual isolation in Islamabad and a possible treason charge.

Upon his return, commentators rushed to condemn him on Pakistan’s influential television talk shows. Then, before the Supreme Court had even heard his side of the story, it barred him from leaving the country, a move that prompted his attorney, Asma Jehangir, to describe the case as “pre-judged.”

The court hearing, which opened Monday, was adjourned until Thursday.

Haqqani denies involvement in the “frivolous and absurd memo,” but the talk of treason has disturbed and upset the former ambassador and his family.

“There are some people who disagree with my husband’s views, but that doesn’t give them the right to question his service to Pakistan or his patriotism,” Farahnaz Ispahani, Haqqani’s wife and a spokeswoman for President Asif Ali Zardari, said in a phone interview Tuesday.

“You’d expect the courts to follow the law and give due process, and not allow this media frenzy to decide the matter,” she said. “I am appalled by the media trial that is going on in this country.”

Haqqani’s delicate balancing act as ambassador began to unravel after the U.S. raid in Pakistan in May that killed Osama bin Laden.

Testifying Tuesday before a Pakistani inquiry relating to the raid, he said that after the attack, U.S. officials were not only unapologetic about having violated Pakistani sovereignty, they were also “intransigent and even threatening in their tone,” demanding that Pakistan provide access to data and people found in the house in Abbottabad where bin Laden was killed.

Meanwhile, he told the inquiry, so intense is the anti-U.S. sentiment in Pakistan that any attempt “to win friends and influence people favorably in the U.S. plays into the hands of those agitating against the U.S. in Pakistan.”

“The Pakistani representative is then cast as going against the wishes and sentiments of the Pakistani people,” he said.

In November, Mansoor Ijaz, a Pakistani American businessman, revealed that in early May he had sent an unsigned memo to Adm. Mike Mullen, then chairman of the Joint Chiefs of Staff, via former national security adviser James L. Jones, asking for U.S. help in preventing a possible military coup.

In return for such aid, the memo promised, Pakistan would bring its nuclear arsenal under a verifiable, transparent regime of control, sever links between the military spy service and the Afghan Taliban, and bring to justice militants accused of attacking the Indian city of Mumbai in 2008.

Ijaz said the memo was dictated to him by Haqqani, on Zardari’s instructions, and he has since released a series of purported BlackBerry Messenger exchanges that he says support his version of events.

The military was outraged and, just as important, apparently saw a chance to dispose of a man it had long been gunning for, analysts say. Mistrust had been especially acute since Haqqani accused the army in a 2005 book of a long-standing symbiotic relationship with radical Islam.

The incident offered the military an opportunity to attack Zardari, Haqqani’s boss and most important backer and an equally bitter foe of Gen. Ashfaq Kayani, the army chief.

Asked to give evidence on the memo affair, Lt. Gen. Ahmed Shuja Pasha, the head of the Inter-Services Intelligence agency (ISI), said he had met with Ijaz, reviewed the evidence and concluded that it indicated Haqqani’s involvement.

Last week, Kayani demanded a full investigation of a controversy that he said had harmed national security, calling it an unsuccessful attempt to lower the army’s morale.

On Friday, however, the former ambassador was thrown a lifeline from the United States in the form of an affidavit from Jones, a copy of which The Washington Post obtained.

Jones undermined Ijaz’s story by testifying that the businessman had contacted him about the proposal “a few days before May 9,” the date on which Ijaz has said Haqqani had first telephoned him with the idea.

Pakistani newspapers have begun to ask why the intelligence agency is not being investigated, along with government officials. In the BlackBerry exchanges, Ijaz said that Pasha, the ISI chief, had traveled to Arab countries in May, where he received permission from their leaders to oust Zardari.

“Many are likely to consider Ijaz’s second charge as serious as the one against Haqqani and Zardari and would expect that the Supreme Court gives the statement equal importance as it proceeds with the memo case,” Pakistan Today wrote in an editorial last Thursday.

So far, that expectation has not been met.