But that doesn't mean Biden can't curtail the conflict and attract some Republican cooperation toward his objectives. He has a chance to do that, for several reasons.
Most important is the combination of personal qualities and experience he brings to the job. Throughout his half-century in public life, Biden has thrived on personal connection with colleagues on both sides of the aisle.
Biden came to the US Senate at a time when ideological diversity within parties encouraged compromise across party lines; he still touts his refusal to judge the motives of political opponents. He served more than two decades alongside Senate Republican Leader Mitch McConnell, his occasional partner in deal-making when Biden served as President Barack Obama's vice president.
That didn't stop McConnell from fiercely opposing nearly all of Obama's agenda, most effectively after Republicans won control of the Senate in 2014. Before the twin Democratic victories in Georgia Senate runoffs on January 5, McConnell was poised to do the same to his old friend Biden.
But now the Democratic Senate majority
has transformed the balance of power. It means Biden's party controls the agenda for committee work and the Senate floor, giving Democrats leverage to craft legislation that maximizes Biden's opportunity of luring a small group of moderate Republicans.
The nature of Biden's immediate agenda -- a $1.9-trillion coronavirus relief proposal
, to be followed by a massive infrastructure proposal -- also maximizes that opportunity. Among the White working-class voters whose flip from blue to red made Trump president in 2016, appeals on bread-and-butter economic concerns resonate far better than values issues such as racial equity or abortion.
Biden won back just 10% of them in November even after a campaign contrasting Trump's divisiveness with his own calls for unity. But the White House bully pulpit gives him a chance to win over more of them on some initiatives, especially with Trump exiled to Florida without access to his social media megaphone.
"This is the best chance we have," says David Shor, a leading Democratic electoral strategist. As a 78-year-old White man rooted in the Main Street of an earlier era, Biden puts the friendliest face on his party's agenda for voters who feel threatened by cultural and economic change.
Consider these results from a Quinnipiac University national poll
last week: 15% of Republicans approve of Trump's impeachment, 17% say White supremacy played a major role in the insurrection, and 33% don't want former president to play a major role within the party in the future. While 67% of Republicans falsely believe Biden did not legitimately win the presidency, 28% acknowledge that in fact he did.
Biden may also benefit from deeper undercurrents of American yearning to move beyond divisions that have been building for years before exploding in violence at the Capitol. Harvard social scientist Robert Putnam, who documented the increasing atomization of American society two decades ago in his book Bowling Alone, has just published a new volume, The Upswing, envisioning the repeat of an historic pattern that would nudge American society back toward shared values.
"The task will not be an easy one, and nothing less than the success of the American experiment is at stake," Putnam writes. That very possibility propelled the improbable optimism of Biden's inauguration last week.
"Don't tell me things can't change," Biden said, his voice laced with emotion, before leaving Delaware for Washington to take the oath of office. "They can, and they do."