Washington (CNN) The ill feeling between Former FBI Director James Comey and the President who fired him burst back into the open in dueling interviews on Wednesday that followed the end of the Robert Mueller investigation.

Their fresh clash revived the mystery of their short, disastrous relationship at the beginning of President Donald Trump's term, which plunged the administration into crisis and led to the appointment of the special counsel. In retrospect, Trump's move in firing Comey was the start of a long-term power play that established the President's dominance over the judicial establishment.

Trump on Wednesday blasted Comey as "a terrible guy" and slammed his leadership team at the FBI as "not clean, to put it mildly," in an interview on Fox News' "Hannity."

William Barr's statement Sunday quoting Mueller as saying the "investigation did not establish that members of the Trump Campaign conspired or coordinated with the Russian government in its election interference activities" and the attorney general's personal determination that "the evidence developed during the Special Counsel's investigation is not sufficient to establish" obstruction of justice represented a huge political win for the President.

But it puzzled Comey that Mueller punted on the question of obstruction, which was largely rooted in his dismissal in May 2017. Trump had said on television he was motivated to fire Comey over the then-FBI director's oversight of the Russia investigation.

"I'm not prejudging it -- I'm just saying it doesn't make sense on its face, and so I have a lot of questions," Comey said in an interview that aired Wednesday on NBC's "Nightly News."

At the time, Trump's sudden decision to fire Comey was widely mocked as the most disastrous political call in decades. But it now appears like the President will escape paying a lasting political consequence for a move that significantly consolidated his own power.

Comey's firing is just one of the stunning twists in the Russia drama that are beginning to take on a new complexion. The late emergence of Barr -- who moved swiftly to manage the end of the Russia investigation -- is another such twist.

In the short term, Trump's dismissal of Comey rid him of a troublesome, powerful figure who assessed that the President wanted to co-opt him into a patronage-style relationship and to infringe ethical barriers between the White House and Justice Department.

In the long term, by exploiting ill-defined norms governing the limits of executive authority, Trump, either by accident or design, may have expanded the power of the presidency itself, setting a significant precedent for the future.

Presidents have the authority to dismiss anyone in the executive branch -- but the situation becomes constitutionally murky if the move appears to be an effort to derail a criminal investigation into their own conduct.

A future unscrupulous commander in chief could use Trump's treatment of Comey as justification for nefarious ends.

"It could send a signal to future presidents that they could do this and get away with it and I think that is a very disturbing possibility," said Jens David Ohlin, vice dean at Cornell Law School. "It seems to be creating a precedent that if a President doesn't like an investigation that is getting close to the President, they can just dismiss the attorney general or the FBI director."

Comey's take

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Comey was on an official trip to the West Coast in May 2017, when he learned about his firing on television. It was one of the first signs that Trump's impulsive leadership style and willingness to test the outer limits of traditional behavior would follow him from the boardroom to the West Wing.

The President's subsequent comment on NBC that he dismissed Comey because of the Russia investigation sparked a sequence of events that at one point seemed as though they could end his presidency itself.

There were immediate warnings that Trump had not only obstructed justice but had compounded his error by telling the nation about it on television.

Comey's departure led to Mueller's appointment a few days later and two years of agony for the White House, which led to the prosecution and jailing of a number of Trump associates while subjecting the nation to a political nightmare.

Foreseeing much of the turmoil, Steve Bannon, once Trump's political guru, told CBS' "60 Minutes" in September 2017 that getting rid of Comey was probably the worst error in "maybe modern political history."

But 18 months later, there is an alternative interpretation: Trump not only managed to rid himself of an FBI director who took an instant allergic reaction to him, but was able to insulate himself from the potentially grave consequences of the dismissal.

Power move

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History may see his conduct not as the act of a blundering neophyte unaware of constitutional norms, but of a President who found a way to amass more power and avoid accountability for doing so.

There are growing questions about Barr's role in the Mueller endgame. His swift assumption of control over the investigation, culminating in his summary of the report, provided a valuable political service to Trump.

His summary set the political narrative allowing the President to claim wrongly that he was totally exonerated and that his claims the probe was an illegal attempt to take him down were justified.

Notwithstanding Barr's summary, it is likely that when Americans do see the report, it will include behavior by the President that is unflattering and possibly unethical even if it does not reach the standard of a criminal conspiracy.

After all, Barr quoted Mueller in his letter to Congress noting that "while this report does not conclude that the President committed a crime, it also does not exonerate him."

Barr told a frustrated Democratic House Judiciary Chairman Jerrold Nadler Wednesday that it would be weeks not months before a fuller version of the report is released. But the period between the initial verdict from Mueller and the full accounting will enable conventional wisdom on the report to gel further.

That's why the attorney general's role has some Democrats and other critics viewing his appointment as another variant of a successful presidential defensive play and power move.

Trump's relentless campaign against his first Attorney General Jeff Sessions was largely motivated by the former Alabama senator's recusal from the Russia investigation.

In his place, Trump was able to confirm Barr, with the help of an obliging Republican-controlled Senate, who wrote an unsolicited memo in June criticizing Mueller's obstruction case as "fatally misconceived."

Fast forward eight months and Barr decided -- after Mueller left unresolved the question of whether Trump obstructed justice -- that the evidence did not suggest that he had.

Barr's motives in the spotlight

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Suspicions about Barr's conduct might only be expelled by the full release of the report and Mueller's underlying evidence.

The obstruction case was always going to be difficult for Mueller to prove, because a case must establish that the perpetrator acted with corrupt intent. Another attorney general might have come to the same conclusions as Barr.

"This is a matter of interpretation," the President's lawyer, Rudolph Giuliani, said on CNN's "The Situation Room" on Tuesday. "You know all the facts about obstruction. You can interpret them several different ways, which is why it was a difficult question."

In Trump's case, the issue was even more complicated since so much of the alleged obstructive behavior happened in public, on television, and on Twitter. But it does seem to be a large coincidence that Trump found a permanent replacement for Sessions who had an expansive view of a President's power to fire subordinates and how such action could bear on an obstruction case.

Barr argued in his June memo that Trump's firing of Comey and his request for him to cut Flynn a break were consistent with the President's authority under Article II of the Constitution, which lays out power over the executive branch of government, of which the Justice Department is a part.

There is a genuine legal debate about whether a President could still be guilty of obstructing justice if his use of his Article II powers is rooted in a corrupt motive.

It's also not going to be clear until the report is released whether Barr was acting on his previous skepticism or whether his ruling on obstruction was purely based on Mueller's findings.

Democrats say that's the reason the full report and evidence must be released.

"We cannot make a judgment on the basis of an interpretation by a man who was hired for his job because he believes the president is above the law and he wrote a 19-page memo to demonstrate that," House Speaker Nancy Pelosi told her caucus in a private meeting Tuesday, according to an aide in the room.