Leading figures in the Russia drama face fateful choices in the coming days and months that could tip America into a political and constitutional abyss. With the midterm elections in the rearview, a sense of foreboding is settling over Washington.
The gravity and consequences of the investigation suddenly seem oppressive, with special counsel Robert Mueller writing his final report and an unchained President Donald Trump aggressively seeking to check him.
New acting Attorney General Matthew Whitaker and the likely next House speaker, Nancy Pelosi, must quickly adapt to new circumstances and powers that have made them vital players at a critical moment of the intrigue.
It is becoming increasingly clear, not least from Trump's raging mood, that the end game of the Russia saga will subject the mechanisms of the US government to extreme stress and test the nation's shattered cohesion.
The President: Disrupt or stand pat
Trump pointed out in his post-election news conference on Wednesday that although he believes the Russia investigation is "very bad for our country" he has so far not shut it down.
"I could have ended it anytime I wanted. I didn't. And there was no collusion," he said.
But there is speculation that he could use Whitaker as a tool to interfere with Mueller's probe or stifle its conclusions, or even to try to fire the special counsel. Any of those options could ignite a constitutional conflagration.
Alternatively, Trump could choose to wait for the final report into allegations his campaign colluded with Russia in 2016 and he obstructed justice to cover it up.
The President has already given an ominous glimpse of his intentions.
Within hours of midterm polls closing, Trump ejected Attorney General Jeff Sessions, who had recused himself from oversight of the Russia investigation.
Trump installed Whitaker above Deputy Attorney General Rod Rosenstein, who has been giving cover to Mueller and his investigators while overseeing the probe.
Some critics interpreted Trump's move as his latest bid to undermine the investigation or remove officials he sees as a threat, in what legal commentators are now calling a "slow motion 'Saturday Night Massacre,' " in reference to Watergate.
There is a building debate over whether Trump's appointment of Whitaker might have been in itself an abuse of power.
Still, there were signs on Thursday that there has been no disruption to oversight of the Mueller probe. Rosenstein's top deputy, Principal Associate Deputy Attorney General Ed O'Callaghan, met lawyers from the special counsel's team in a regular biweekly meeting, a source familiar with the matter told CNN's Laura Jarrett.
The source explained that while Whitaker has ultimate oversight authority as the acting attorney general, the day-to-day running of the probe is still being handled by Rosenstein's office. "It's business as usual," the source said.
The President is on dangerous ground if he decides to pressure the investigation.
If it later comes out that Trump by design put Whitaker in position to thwart the investigation, he could provide more evidence that he is guilty of a corrupt purpose to obstruct justice.
"That will send him down a path that for the next few years that would tie up his presidency in ways that are not in his best interests legally or politically," said Michael Zeldin, a former senior Justice Department official, with a touch of understatement on CNN International on Thursday.
The new acting attorney general: Suddenly on the hot seat
CNN revealed on Thursday that Whitaker has publicly shot down the idea that Russian interfered in the 2016 election -- contradicting multiple Mueller indictments.
Now, he is suddenly thrust into the most high-stakes legal, political showdown involving different branches of government since Watergate.
He has the power to narrow the investigation and limit the budget for the special counsel's team. He could refuse requests by Mueller to request indictments or to subpoena testimony from the President.
He could try to stifle publication of Mueller's final report or could try to keep it from Congress.
Michael Conway, counsel for the House Judiciary Committee during Watergate, said that the most sinister threat to Mueller may be a quiet attempt to suppress his work by Whitaker out of sight of Congress or the public.
"The concern would be that behind the scenes, he would in a whole variety of ways thwart the investigation without the issue of a public firing, without the issue of a cataclysmic event that would generate immediate political backlash," said Conway, now a professor at the Medill School of Journalism.
Democrats demanded Whitaker recuse himself over his previous criticism of Mueller -- a largely academic exercise since it's obvious his main attraction to Trump is that he is not prevented from overseeing the investigation.
The first sign that Whitaker is acting against Mueller could come if there are no indictments in the weeks to come or signs of activity at the grand jury.
If indictments follow, it could be a sign Whitaker stepped back.
One interpretation of Trump's swift rejigging of the Justice Department after the midterms is that the President did not want time for Mueller to produce any indictments after the end of a self-imposed hiatus during the political season.
Whitaker has walked into tremendous personal pressure. Trump has made no secret of his visceral anger at Mueller, and has shown -- in his dealings with fired former FBI Director James Comey and Sessions -- that he expects loyalty to him to supersede everything.
Whitaker will face the same demands and is in a far weaker position than either Sessions or Comey, who enjoyed personal power bases and reputations and alliances forged after decades of public service.
Once he is read into the Mueller investigation, the new attorney general will face an ethical question. Will he tell Trump what he knows even though doing so would cross an ethical line?
But Whitaker is also in a legally vulnerable position.
He risks being pulled into a conspiracy if the President or other officials seek to unlawfully obstruct the investigation. He is likely to be hauled up to Capitol Hill by the new Democratic House majority in the new year and be forced to testify under oath about his appointment. He might remember that Nixon Attorney General John Mitchell was convicted for his role in Watergate.
At some point, Whitaker may face the ultimate dilemma for a Washington law enforcement official caught in a scandal. Does his duty to the Constitution or his President take priority?
Mueller: Keep calm and carry on?
Mueller's silence has been his best defense against ferocious efforts by Trump and the conservative media machine to draw him into the political swamp.
So it is, and always will be, impossible to know what he thinks about the new Justice Department hierarchy.
CNN reported Thursday that the special counsel had started writing his final report. Recent weeks grand jury activity indicates that Mueller is trying to find out whether Trump's longtime adviser, Roger Stone, knew in advance that Wikileaks would release hacked material during the 2016 campaign.
But there was also a reminder on Thursday that his freedom to act could be in doubt when Michael Dreeben, a prosecutor for the special counsel's office acknowledged in court that Whitaker could change or rescind the May 2017 order that appointed Mueller.
People who have worked with Mueller believe he has already prepared for the suppression or shutting down of his work. He has for instance farmed out the tax fraud case against Trump's former personal lawyer Michael Cohen to prosecutors in New York. There was speculation in Washington recently that sealed indictments against targets of the probe may already have been filed.
Mueller has some protection in his initial charge from Rosenstein.
If Whitaker takes steps to constrain Mueller, he would be required to explain to the leadership of the Senate and House Judiciary committees why he did so.
In theory, he can also only be fired for cause or misconduct.
In the last resort, his resignation would provoke a political firestorm that could lead to impeachment proceedings against the President. But it would also risk the possibility that much of his work does not see the light of day.
Pelosi: The institutional check on Trump
Pelosi is likely to be the next House speaker and will have the power to have an institutional check on the administration.
She will have authority over House committees that will provide oversight of Trump and the Justice Department. On Thursday, she held a conference call with new and existing members to discuss the Sessions firing and Whitaker's appointment, sources told CNN.
Democrats have already indicated that they will investigate Trump's appointment of Whitaker. They are likely to reinvigorate the House Intelligence Committee's Russia investigation when they get the gavel.
Pelosi will be pulled in multiple directions. She faces an imperative to respond to any attempts by Trump to curtail Mueller. But as preparations begin for the 2020 election, she must guard against actions that could be portrayed by the GOP as overreach.
At the same time, she will face pressure from her left from liberal activists who are already demanding Trump's impeachment.
"I don't think we should impeach a president for political reasons. But I don't think we should not impeach him because we think it's politically ... impeding for us to do so," Pelosi told CNN's Chris Cuomo in an interview Thursday.