Miss me now? Barack Obama’s absence has probably never been felt so keenly by his millions of supporters.

They feel sure the former US president would have taken a very different approach, and struck a very different tone, from Donald Trump in handling the once-in-a-century crisis of the coronavirus pandemic.

But while for now Obama is hunkered down at home with few tools beyond Twitter, a return to the political stage could be imminent. With his former vice-president, Joe Biden, this week in effect confirmed as the Democratic candidate in this year’s presidential election, Obama’s endorsement is eagerly awaited.

“There’s no doubt the majority of Americans are yearning for Barack Obama’s leadership right now,” said Moe Vela, a former senior adviser to Biden at the White House. “It’s palpable. You can feel that around the country. He led us through the financial crisis, Ebola and several other crises. For eight years he stood at the podium and said, ‘I take responsibility.’ Now we have the antithesis of that.”

Obama inherited an epic trauma of his own, the 2008-09 financial meltdown, which, supporters claim, would have developed into a Great Depression but for the actions of his administration. He also had to deal with an outbreak of swine flu, which killed an estimated 12,469 Americans, according to the Centers for Disease Control and Prevention.

Ebola in west Africa in 2014-16 raised further alarm but only 11 people were treated for the virus in the US. Obama’s White House Ebola “czar”, Ron Klain, is now a regular TV and podcast critic of Trump’s disorganized response to the coronavirus. On Wednesday, Klain tweeted a video of Obama in 2014 warning of the need to be ready for the next pandemic.

Obama’s former national security adviser Susan Rice told the Washington Post that Trump’s failures “cost tens of thousands of American lives”.

The ex-president himself, however, declines to speak out directly against his successor. But he has tweeted more frequently than usual: 33 posts in the past month, many of which offer advice on stopping the virus spread, pay tribute to healthcare and other essential workers or share inspiring stories.

Democrats watching the catastrophe unfold can only imagine what might have been. Vela, who sat on the White House emergency preparedness and continuity of government working group, said: “I’m sure President Obama is champing at the bit. He knows what should be happening. That’s why you hear such frustration in the voices of those who worked for him.”

Can you ever remember Obama speaking gibberish? Larry Sabato

Obama’s admirers say he was often at his best in the face of tragedy. He spoke movingly and wept after the killing of 20 children and six staff members at Sandy Hook elementary school in Newtown, Connecticut. Honoring nine African Americans shot dead at church in Charleston, South Carolina, the president burst into a rendition of Amazing Grace.

Trump not been seen crying in public. His daily coronavirus taskforce briefings seldom dwell on the monumental loss of life and human tragedy at the heart of the pandemic. But he does constantly praise his administration’s response – “I’m a cheerleader,” he said this week – and his own TV ratings.

Vela, a board director at TransparentBusiness, commented: “This is a man who hasn’t expressed one iota of empathy or compassion to the people who have lost loved ones in this pandemic. He is obsessed with Obama, he blames everything on Obama, and it’s obvious where it comes from: he can’t even shine Barack Obama’s shoes.”

The two presidents have always been polar opposites. Larry Sabato, director of the Center for Politics at the University of Virginia, added: “Trump’s narcissism is overpowering: everything is about him. Obama was a very controlled person. He would have given you the facts and nothing more. He would have been perfect for this.

“Remember the school shooting in Connecticut. Obama did cry, as any human being would after children were killed, but he was still able to speak carefully and in complete sentences. Trump’s briefings are one-third true, one-third misleading and one-third complete gibberish. Can you ever remember Obama speaking gibberish?”

Typically in national emergencies, presidents make contact with their predecessors. John F Kennedy briefed and consulted with Dwight Eisenhower during the Cuban missile crisis. All five living former presidents came together to raise funds for hurricane relief in 2017 . Trump, however, has made clear he has no intention of speaking to Obama about the virus because “I don’t think I’m going to learn much”.

But he has frequently sought to blame Obama for the leaving the country unprepared, even though it was Trump who disbanded the national security council’s pandemic preparedness unit. And this week, when Senator Bernie Sanders dropped out of the Democratic primary, he speculated on when Obama will endorse Biden.

“I don’t know why President Obama hasn’t supported Joe Biden a long time ago,” Trump told reporters. “There is something he feels is wrong. I’m sure he’s got to come out at some point because he certainly doesn’t want to see me for four more years. We’re not – we think a little bit differently.”

Few would disagree with that assertion. Trump is not alone in wondering why Obama has not already endorsed Biden. But it is not the first time: in 2015, Obama reportedly decided Hillary Clinton should be his successor and helped steer Biden away from running.

Sabato said: “It’s about time, whenever he does it. I know there were many people close to Joe Biden who were miffed but they didn’t say anything because the last thing they wanted to do was to antagonize the Obamas.”

Barack Obama with the former first lady Michelle and Joe Biden with Dr Jill Biden, his wife. Photograph: Kevin Lamarque/Reuters

Obama kept his powder dry during a grueling primary contest that involved 28 candidates and may make Biden wait a while longer.

Sabato added: “If Obama endorsed Biden now, it would disappear into the pandemic black hole. So why would he waste that card?”

The endorsement would presumably come before the Democratic national convention in Milwaukee, which has been postponed from July to August because of the virus. If it does go ahead, Obama and his wife, Michelle, would have a crucial role to play in making Biden’s case, especially to many younger voters who flocked to Sanders in the primary.

David Litt, a former Obama speechwriter and author of the upcoming Democracy in One Book or Less, said: “Barack Obama is a very good person to introduce Joe Biden to younger voters. There’s an old Bill Clinton saying: sometimes you need someone else to brag on you. Obama is the perfect person to brag on Biden. He can speak to Biden’s abilities as a politician and is more trusted than anyone in the country right now.”