Americans are hugely proud of the peaceful transfer of power that has happened every four years since the founding of their republic.
Certifying the Electoral College vote count should have been just a formality, a ritual part of that all-important process.
Instead it was the focus of protest and overshadowed by violence.
Donald Trump helped cause the unrest by calling the election fraudulent, trying to persuade his vice president to subvert the certification and urging his supporters to protest.
That break with the tradition of a peaceful, co-operative handover of government will be one part of his legacy.
Another is a deeply divided America whose people seem to believe in several conflicting realities.
An America where more than 50% of Republican voters, according to one poll, believe Mr Trump rightfully won the election even though attempts to prove allegations of fraud have been rejected in the courts.
Another is the record of incompetence in handling the coronavirus pandemic that has caused so many deaths.
Joe Biden has set himself the challenge of making America lead the world again.
To do so he has to restore allies’ confidence in America and Americans’ belief in themselves.
He can work hard to improve America’s record on fighting the virus and its economic impact.
He can try to unite the country and heal its wounds and divisions.
But the scenes of violence in Washington will be hard to recover from.
And the perception held by millions of Americans despite the lack of any evidence that they were robbed of an election will linger on and fester.
If Mr Biden had hoped his predecessor would make the job easier by receding from view gracefully, this week will have dispelled him of any illusions.
Donald Trump looks unlikely to go quietly.