When Donald Trump Jr was first asked about his meeting with a Russian lawyer during the election campaign he crafted a statement explaining it had been held to discuss adoption policy.
As more details emerged, he admitted that Natalia Veselnitskaya had said she had compromising information on Hillary Clinton, his father’s election opponent, but that she was vague on specifics and the offer amounted to nothing.
Since then the drip, drip, drip of information has continued.
E-mails showed how he leapt at the chance to meet a woman carrying compromising material as part of a Russian government effort to help his father — the first time a Trump campaign member has been shown as a willing collaborator with the Kremlin — and the cast of characters in the meeting has expanded to include a lobbyist suspected of being a former Russian counter-intelligence officer.
By Saturday morning, the total number of people in the room during that June 2016 meeting in Trump Tower had grown to eight. Alongside Mr Trump Jr, there was Jared Kushner, the president’s son-in-law, Mr Trump's then campaign manager, Paul Manafort, Ms Veselnitskaya, Rinat Akhmetshin, the lobbyist who denies ever having been trained as a Russian spy, Rob Goldstone, a British publicist who brokered the meeting, a translator and an unnamed member of the Russian family who helped set up the get-together.
The never-ending stream of revelations highlights how the White House has been unable to shrug off allegations that the campaign worked with Russia to gain an advantage over Mrs Clinton in last year’s election.
It has emboldened the president’s critics, left his administration struggling to advance its legislative agenda and mystified political strategists.
Lanny Davis, who worked as special counsel to president Bill Clinton during his impeachment hearings, said: "No successful crisis management model works the way they are doing things.
"If your mission is to control a story or try to end a story, you need to tell it early, tell it all and tell it yourself."
Instead, the result is that every new revelation is treated by half of America's voracious cable news networks as the latest sensational twist in Mr Trump’s downfall, and as evidence of journalists’ bias against the president by the other half.
Although Republicans say they still see no evidence of collusion with Russia other than amateurish and incompetent efforts to hide details of the meetings, Democrats scent blood.
They have turned their attention to Mr Kushner, who they believe may be the most vulnerable member of the president’s core team.
He has twice had to update information submitted on security clearance application form SF-86 after omitting to mention contacts with foreign governments.
Intentionally concealing or falsifying answers is a criminal offence subject to up to five years in prison.
Mr Kushner’s lawyers insist it was an innocent mistake but Democrats are demanding he lose his security clearance.
Nancy Pelosi, who leads Democrats in the House of Representatives, said there was now “cold, hard, evidence” that the Trump family “eagerly intended” to collude with outsiders — possibly with Russia — to influence the elections.
“I … call for the revoking of the security clearance for Jared Kushner. It's absolutely ridiculous that he should have … that clearance,” she said.
Don Beyer, a Democratic congressman from Virginia, went further. "Jared Kushner must resign. If he will not, he should be fired."
Some Republicans have also expressed their exasperation at the way the crisis is being handled. In particular, they have focused on the way family members and figures with no previous political experience have allowed themselves to be caught out through naivety.
Bill Flores, a Republican congressman from Texas, said: "I'm going out on a limb here, but I would say I think it would be in the president's best interest if he removed all of his children from the White House. Not only Donald Trump Jr, but Ivanka and Jared Kushner."
Campaigners familiar with the Russian cast of characters say the Trump campaign allowed itself to be targeted by the Kremlin as part of Moscow's efforts to get the US to lift sanctions contained in the Magnitsky Act.
The legislation was designed to punish officials responsible for the death of lawyer Sergei Magnitsky in a Russian prison in 2009.
Bill Browder, a hedge fund manager who asked Magnitsky to investigate a corruption scandal, said repealing the act was Russian president Vladimir Putin’s priority in relations with Washington.
He added that the presence of Mr Akhmetshin, the Russian-American lobbyist, showed the importance of the Trump Tower meeting.
“Basically, it only makes it more clear that the Russians were trying as hard as they could to pursue the agenda of getting rid of the Magnitsky Act by sending in one of their trusted agents,” he said.
