When Joe Biden finally recovers from Covid at his beach house and returns to the Oval Office, likely later this week, he risks being the lamest of lame ducks for his remaining six months in office.
But the 81-year-old, smarting from the humiliation of having to drop his reelection bid, could still influence the success of Vice President Kamala Harris's campaign and push to resolve key foreign policy issues.
"We're not quite lame duck. It's wounded duck," Peter Loge, director of George Washington University's School of Media and Public Affairs, told AFP.
All US presidents leaving office face a period of limbo between election day in November and inauguration day in January.
For Biden, however, an unusually long period of some 100 days looms when voters, politicians and foreign leaders will all have their eyes on the horizon instead of on him.
Yet Biden's pledge in his stepping-down letter on Sunday to "focus solely on fulfilling my duties as president for the remainder of my term" does not have to be an empty one.
"He's still the president of the United States, he's in charge. He obviously wants to do things that set Vice President Harris up for success," said Loge.
That puts the onus on Biden to keep pushing the key domestic threads that have run though his presidency, such as lowering inflation, keeping unemployment down and dealing with high pharmaceutical prices.
Crucially, Biden can still appoint judges who could then stay in place for decades.
This remains a key lever of power in a deeply polarized country where an increasingly politicized judiciary decides on issues like women's rights and abortion.
"He has a real incentive to end strong, so that Harris can look strong until November" as she faces Republican former president Donald Trump, added Loge.
With seemingly intractable wars raging in Gaza and Ukraine, Biden may also turn his focus abroad for his final days in the Oval Office.
"What I would expect is that Biden will concentrate on foreign affairs," David Karol, who teaches government and politics at the University of Maryland, told AFP.
"Presidents have made major moves in foreign policy in the lame duck phase," he said, citing among others George H.W. Bush's decision to remove US troops from Somalia in the dying days of his one-term presidency.
A major prize would be a ceasefire in Gaza, which Israel has pounded since the October 7 attacks by Hamas.
Biden risks highlighting his lame-duck status with a planned meeting with Israeli Prime Minister Benjamin Netanyahu this week -- if his recovery from Covid allows it.
The two leaders have had strained relations over Netanyahu's conduct of the war.
But a deal would be "helpful" to Harris's candidacy "because that issue has proven divisive in the Democratic Party," said Karol. "And she's maybe a little less tied to the policy than he is."
On Ukraine, Biden may be keen to secure the multi-billion-dollar aid package for Kyiv's fight against Russia, amid fears that if Republican Donald Trump wins he could abandon it.
The one final power that an outgoing president can wield is potentially the most sweeping, but also the most controversial -- the presidential pardon.
Biden's beloved but troubled son Hunter was convicted in June on charges of lying about his drug addiction while buying a handgun, and faces up to 25 years in prison.
Candidate Biden pledged not to pardon 54-year-old Hunter or commute any sentence -- but his thinking could change post drop out, and in an election race like no other in modern US history, anything is possible.
