Throughout the Trump-Russia investigation, the core question -- the question that mattered above all others -- was whether President Trump or his associates colluded with Russia to try to influence the 2016 election.
If there were proof of that, the effect on Trump's presidency would have been devastating, and possibly fatal.
The problem, for the confederation of Democrats, pundits, Obama holdovers and NeverTrumpers who hoped to see that result, has been that so far, after a lot of investigating, no evidence has emerged that collusion actually occurred.
Although they allowed that previously unknown proof could always emerge, last week some of the lawmakers most deeply involved in the investigation, and most closely in touch with the intelligence community and law enforcement working on the probe, conceded that there appeared to be no there there.
That was then. Now, rather than focusing on alleged collusion, the thrust of leaks in recent days has been directed almost exclusively toward building a case of obstruction of justice against the president, charging that he actively tried to derail the investigation into his campaign and his associates. More and more, day after day, Trump's adversaries believe that, when it comes to bringing down the president, it might not matter if collusion occurred or not.
A cover-up would be enough to do the job.
The Trump-Russia case could become the ultimate illustration of the old Washington saying that it's not the crime, it's the cover-up. In this case, there might be no underlying crime at all.
The latest story in the cover-up timeline broke Monday night in the Washington Post. Citing current and former officials, the paper reported that Trump called the Director of National Intelligence and the head of the National Security Agency to enlist their help to "push back" against the FBI investigation and to "publicly deny the existence of any evidence of collusion during the 2016 election."
Before that came a spate of reports and developments, all arising out of Trump's May 9 firing of FBI Director James Comey.
First, the White House portrayed the firing as 1) not Trump's doing, and 2) not related to the Russia investigation.
Then Trump told NBC's Lester Holt that he had in fact decided to fire Comey because "this Russia thing with Trump and Russia is a made up story."
Then, with accusations of obstruction in the air, Deputy Attorney General Rod Rosenstein appointed a special counsel to investigate the Russian affair.
Rosenstein specifically gave that prosecutor, former FBI Director Robert Mueller, authority to pursue any "federal crimes arising from the investigation" and specifically referenced 28 CFR 600.4(a), which is the part of the Code of Federal Regulations dealing with special counsels and obstruction: "The jurisdiction of a Special Counsel shall also include the authority to investigate and prosecute federal crimes committed in the course of, and with intent to interfere with, the Special Counsel's investigation, such as perjury, obstruction of justice, destruction of evidence, and intimidation of witnesses; and to conduct appeals arising out of the matter being investigated and/or prosecuted."
Then the New York Times reported that Comey wrote contemporaneous memos of his interactions with the president, and that during one of those interactions Trump asked Comey to drop the investigation into fired national security adviser Michael Flynn.
Then the Times reported Trump, in an Oval Office meeting, bragged to Russia's foreign minister and ambassador to the U.S. that firing Comey relieved Trump of "great pressure" in the Russia investigation.
As each revelation came, there was more talk of obstruction.
(A Google search of "Trump" and "obstruction of justice" Monday night drew 597,000 hits.)
Democrat after Democrat suggested Trump might have engaged in obstruction, while the list of Democrats calling for impeachment grew long enough for party leaders to worry about the situation escalating too soon. The newest stories will do nothing to slow things down, even with the president on a foreign trip.
Before Trump fired Comey, a likely conclusion of the Russia affair was coming into view. Flynn would be in trouble for his connections to Turkey and possible violation of the Foreign Agents Registration Act. Former Trump campaign head Paul Manafort would be in trouble for some sort of sleazy business dealing in Ukraine. Maybe another figure or two from TrumpWorld would get into trouble, as well, but in ways tangential to the investigation. There would be scalps for Democrats to celebrate, but the most consequential issue -- collusion -- would end in nothing.
That was before Comey was sacked.
Now, the investigation has taken what is for Trump a more ominous turn. Focusing on alleged obstruction, the president's enemies no longer have to find an underlying crime to attempt to remove him from office.
All the while, some Republicans have found themselves asking over and over: But what about collusion? Remember that? If there's no crime at the bottom of the Russia affair, then isn't all of this just much ado about nothing?
The answer is no.
Certainly Trump has good arguments to make in his defense, beginning with what legally constitutes obstruction. But after the last two weeks, his supporters can no longer assume that his detractors will have to find an underlying crime to make big trouble for the president.