In the last 72 hours, the White House has been turned into a fortress. Newly erected nine-foot high fencing has given the US presidential residence the threatening look of a military compound. Outside the gates mayhem reigns with protests in every state.
Wounds older than the US civil war were torn wide open by George Floyd's death - gashes that never truly healed but were simply plastered over. Donald Trump's response to the anger on the streets - including one bizarre claim that Floyd would hopefully be "looking down" saying "this is a great thing that's happening to our country" - has made the situation significantly worse, for the nation and himself.
Up until last week, Trump's control over the Republican party was assured. With few exceptions, the party establishment has been fully supportive of, and therefore complicit with, his actions.
That's beginning to falter.
Last Tuesday, his former defence secretary Jim Mattis issued a strong criticism of his former boss, declaring: "We must reject and hold accountable those in office who would make a mockery of our constitution."
Last Wednesday, his current defence secretary Mark Esper openly disagreed with his boss's threat to send the US military into various states - saying that military troops should not be sent to respond to protests in American cities.
On the same day, the Trump-appointed chief of staff of the US armed forces, General Mark A Milley, issued a memo to his commanders to affirm that all branches of the military take an oath to defend a constitution that gives Americans "the right to peaceful assembly".
And last Thursday, Alaska's Republican senator Lisa Murkowski refused to confirm that she will vote for her party leader in November.
Small cracks. The vast majority of the Republican establishment is still fully behind Trump. Noteworthy cracks, nonetheless.
The US president, meanwhile, is in full retreat to his familiar bunker of racial politics and Christian conservatism.
The dramatic walk, flanked by secret service, from the White House to St John's Church to hold up a Bible, together with his photoshoot with the first lady in front of the John Paul II National Shrine were designed to appeal to evangelical Christians.
It might seem strange for a man - who once couldn't name a single biblical verse - to cloak himself in the clothes of Christianity, but it makes political sense. Polling in 2017 showed that 48pc of Republicans felt Christians faced "a lot of discrimination" in America. And 43pc believed white people endured the same.
The corresponding figure for black people? Twenty-seven pc.
No objective, logical supportive evidence for these beliefs can be found. But the absence of logic doesn't change the emotions these voters experience. They feel discriminated against. It takes a shameless politician to play to this emotion, to embolden it, with a straight face.
Enter Donald Trump.
He started his presidency by whistling to the "forgotten man" in his inauguration speech - a tactic reminiscent of Richard Nixon's ''silent majority'' oration in 1969.
Against a background of anti-war and civil rights protests, Nixon successfully enlisted white voters who supported neither. His chief domestic aide John Ehrlichman admitted in 1994 that the strategy was specifically about race: "The Nixon campaign in 1968, and the Nixon White House after that, had two enemies: the anti-war left and black people." Clearly, Trump wants to emulate Nixon. But two key differences separate the ''silent majority'' era from today - the lack of silence, and the lack of a majority. Central to Nixon's strategy was the outward appearance of respectability and nuance, and the existence of a significant majority of voters there to respond to his whistle. Trump will find that a difficult play to execute today.
Polling shows a majority of Americans approve of the protests (64pc in most recent surveys), while disapproving of their president.
What Trump does have in his corner is a vocal and motivated minority. And they might be enough. Under pressure from worrying internal polling (he's currently neck-and-neck in direct match-ups with Joe Biden in Republican states like Texas, Georgia, and Arizona), he has run back to the core base of supporters who've been constant in their approval. He's banking that a historic turnout of these enthusiastic fans will be enough to retain his White House residency. Any attempt to change his message to increase his appeal beyond his 40pc base has been abandoned.
However, Democratic-leaning voters now have no doubt that Trump's regime is to be taken seriously. The American president's actions of the last week should have removed any remaining hint of complacency from the 2020 picture - a significant change from the Trump/Clinton election.
Therefore, for those who are against Donald Trump's actions, any space for a morally justified vote for a third party candidate, or a principled decision to not vote (''because they're all as bad as each other''), has been removed.
In 2016, Democratic turnout fell from 2012 levels in key demographics, while 5pc voted for third-party candidates.
To be successful, Democrats must make sure nothing remotely like this reoccurs.
Joe Biden - since yesterday the official Democratic nominee - isn't a perfect candidate. But it's him or Trump. To vote any way other than Biden is to vote for a second Trump term.
This obvious reality has to be central to any successful Democratic message. One of the campaign messages needs to be that staying at home (or voting for a Green or Libertarian candidate) is a de facto vote for Trump.
This is vital, as Biden's primary polling weakness is the lack of outright enthusiasm for him. Only 24pc of his supporters are ''very enthusiastic'' about supporting him, compared to 53pc for Trump.
But this is a flaw only if his campaign fails to convince the electorate that this election is a referendum on Trumpism rather than a traditional race.
Americans last week showed how primed they are for such a plebiscite - you don't take to the streets for the status quo. They don't all need to be moved by love of Biden, they can be motivated by anger at Trump.
In 1884, Grover Cleveland was chosen to be the Democratic candidate in the presidential race. Only three years previously he'd been a mere city mayor. His Republican opponent, James Blaine, had been plagued by accusations of corruption - but Cleveland had a reputation for honesty and integrity.
The newspaper of Joseph Pulitzer, the New York World, famously listed four reasons to explain their support of his candidacy: "1. He is an honest man. 2. He is an honest man. 3. He is an honest man. 4. He is an honest man."
An element of the Democrats' pitch is similar and as simple. "1. He's not like Trump. 2. He's not like Trump. 3. He's not like Trump. 4. He's not like Trump."
In the midst of this chaos, Biden must present himself as the empathetic antidote to Trump's reign.
He must convince those protesting that he can deliver the solutions to the systemic racism and embedded inequality that has brought them to the streets for 13 consecutive days. And that, whatever his flaws, he will continue to listen, learn and act. America will become more divided before November 3. The chasm will widen. Trump will try to wring out every possible vote from his minority base - further inflaming division.
The task of stitching the union back together will be a monumental challenge. The question is, will the attempt start in November or in 2024?
Lorcan Nyhan is head of training at the Communications Clinic