Joe Biden's campaign is built on two ambitious promises: Get the coronavirus under control, and get America back to normal.The catch: Both will be enormously difficult to deliver.The big picture: The election is a referendum on President Trump. But if Biden defeats him and heads to the White House, his honeymoon won't last long.The nation's health and economic COVID-19 recovery — and whether our politics remains this divided and broken — will eventually become bases on which Biden, Kamala Harris and Democrats are judged.As Barack Obama's vice president, Biden has seen a tamer version of this movie before. They inherited a war Obama ran against and a financial crisis that overshadowed much of their campaign ambitions.Biden recently articulated the priority for a prospective first 100 days in office during an interview with Pod Save America: "Get control of the virus."And in his final presidential debate against Trump, Biden declared: "220,000 Americans dead. If you hear nothing else I say tonight, hear this: ... Anyone who's responsible for that many deaths should not remain as president of the United States of America." That line may come back to haunt him; the U.S. death toll could reach 400,000 by February 2021, days after the next president is inaugurated. And there will be more on his watch even under the best of circumstances.Between the lines: Biden's broader promise to return the U.S. approach to pre-Trump parameters is complicated by the sheer volume of Trump-era actions.Trump has signed nearly 200 executive orders since 2017. And his administration has taken more than 400 executive actions on immigration alone.He's also placed hundreds of judges in courts across the land.Biden has vowed to undo Trump's withdrawal from the World Health Organization and the Paris climate agreement, the 2017 tax cuts, the travel ban targeting mostly Muslim-majority countries, and Trump's immigration policies, including child detention centers and moves to construct a physical U.S.-Mexico border wall.What they're saying: “When Obama got elected in 2008 I said he got dealt the most difficult hand since Franklin Roosevelt, and that record will only have stood for 12 years," David Axelrod, former senior adviser to Obama, told Axios. "There’s no doubt in my mind that if Biden is elected, what he will inherit is harder.”His advice to Biden: Think very carefully about the sequencing of the things that you do. Make sure that you’re telling a big story — details are essential but the narrative is crucial. “We got a little bit too balled up in the details," Axelrod said of the Obama years. "At times we lost the narrative, but the narrative is really important.”"There is a palpable decency and empathy, he has a reverence for the institutions of democracy and a connection to people. Those things will play big in the post-Trump era. It’s not a substitute for tangible progress — he’ll have to show that, too — but there will be a period of goodwill for him.”Others don't see a return to more normal times. "I don't think it's realistic that Biden in four years could unroll everything that Trump did," Sarah Pierce, a policy analyst at the nonpartisan Migration Policy Institute, told NPR."The real problem is the societal impact," Philippe Reines, longtime Hillary Clinton advisor, told Axios. He said Trump's legacy includes "arming four out of every 10 Americans with the ultimate two-word out to any inconvenient topic: 'Fake news.' That’s permanent."For the record: "Joe Biden has proved throughout his entire career that he can rise to the moment and deliver monumental progress," said Matt Hill, Biden campaign deputy press secretary. "This moment in American history requires a leader with the ambition, vision, and spirit to unite our nation and build the economy and the country back better than ever before. Joe Biden is that leader."What we're hearing: Some Democrats think if Biden focuses on a coronavirus relief package, that could open the door to activating on other progressive priorities — like canceling student loan debt, expanding Social Security benefits, and bolstering union jobs and workers. The bottom line: Biden may have other successes if he wins the presidency. But the odds of a quick turnaround on the coronavirus and America's bitter divisions are pretty low — and that's the high bar he's set for himself.