This recent history now feels like an eternity ago. The dynamics of American politics, and Trump's re-election hopes, have been transformed by two seismic events over the past fortnight: Trump's haphazard response to the coronavirus outbreak, and the stunning resurrection of Biden's political career. The emerging view that Trump was gliding towards a second term has been upended by a plummeting stock market and the emergence of a potentially formidable opponent. "Bad news for the country is bad news for the incumbent," Mark Mellman, a veteran Democratic pollster, says. "The prospect of a recession is a calamity for Donald Trump." 'Down close to zero'

The Trump administration's response to the coronavirus started without any major hiccups. On January 31, the administration declared a public health emergency and said it would deny entry to foreign citizens who had travelled to China in the previous 14 days. This was seen by some at the time as a potentially xenophobic overreaction. But the decisive action no doubt saved American lives. Since then, the administration's response has spiralled out of control. More than any other event in his presidency, the outbreak has exposed the inherent flaws of Trump's approach to governing – his fondness for falsehoods, chaotic decision-making and disregard for expertise. As the number of coronavirus cases has mounted in recent weeks, Trump has appeared in almost complete denial about the seriousness of the problem.

In late February, Trump falsely claimed that confirmed cases were "going very substantially down" and would soon be "down to close to zero". Instead, the number of cases predictably shot up. Last week, Trump toured the Centres for Disease Control and Prevention headquarters in a red "Keep America Great" cap and claimed: "Anybody who wants a test can get a test." Loading Replay Replay video Play video Play video That wasn't true, as Trump's top health experts have pointed out. Anthony Fauci, the US government's highly respected infectious diseases expert, this week described the lack of test kits available in the US as a major failing. As more Americans get tested in coming weeks the number of confirmed cases – about 1500 currently – is expected to explode.

'Major economic steps' The administration's attempts to limit the economic fallout of the outbreak have been just as ham-fisted. On Monday (Tuesday AEDT) Trump made a surprise appearance at the White House's daily coronavirus briefing. Wall Street had just recorded its biggest losses since the 2008 global financial crisis. Trump said his administration was preparing to announce a "very dramatic" economic stimulus package, including a payroll tax cut and support for the hospitality and tourism sectors. "So I will be here tomorrow afternoon to let you know about some of the economic steps we’re taking, which will be major," Trump said.

Loading Stock prices rose the next day in anticipation of the announcement. But it never came. The White House, in fact, was nowhere near ready to announce its economic response. Investors realised they had been hoodwinked and the markets tumbled again the following day. That night Trump sat down in the Oval Office for a rare national television address. Rather than calming a frightened nation, his remarks intensified the growing sense of panic. Trump announced that all travel from Europe would be suspended for 30 days, causing Americans holidaying overseas to fear they would be left stranded on the other side of the world.

The Department of Homeland Security later clarified that the ban only applied to foreign nationals. Trump also suggested that cargo was being banned from Europe; he later tweeted that the restrictions applied only to people. Loading Trump said private healthcare companies had agreed to cover the cost of treating patients with the virus. In fact, they have agreed to cover only the cost of the tests. "That speech was impossible to follow; it was completely garbled," says Larry Sabato, the director of the University of Virginia's centre for politics. "He can't even read off a teleprompter."

The US stock markets responded violently, recording their worst days since the 1987 stock market crash on Thursday (Friday AEDT). "At this point in time, all of the market cap gains seen since President Trump’s election victory have been wiped out," Paul Hickey, founder of investment firm Bespoke, wrote in a note. It was terrible news for Trump, who has repeatedly cited stock market gains as evidence of his administration's economic prowess. Consultancy firm Capital Economics now projects that the US economy will shrink 0.6 per cent this year, rather than expanding 1.8 per cent as previously forecast. Larry Sabato, who runs a respected election forecasting service, expects the November election will be close. But he says a recession would seriously dent Trump's hopes of a second term.

"Trump's biggest sell has been the economy," he said. "If people don't see it as strong, he is going to bear the brunt of that." Is 'Sleepy Joe' a sleeping giant? As US sharemarkets tumbled on Thursday (Friday AEDT), Joe Biden made his own televised address about the coronavirus. Loading Replay Replay video Play video Play video Nicknamed "Sleepy Joe" by Trump, the former vice-president is not the most fluent orator. But his coronavirus address was sober, fact-based and authoritative.

"I can promise you that when I’m president, we will prepare better, respond better and recover better," Biden said. "We will lead with science. We will listen to experts and heed their advice. We will rebuild American leadership and rally the world to meet global threats. And I will always, always tell you the truth." Biden was speaking as the Democrats' presumptive presidential nominee – a prospect that seemed far-fetched just a few weeks ago. Before Biden's thumping victories in South Carolina and on Super Tuesday, Bernie Sanders was on track to be the party's nominee. It was a prospect that terrified the so-called "Democratic establishment" and, as it turned out, a majority of rank-and-file voters. While he has to increase his appeal to young voters, Biden has been assembling an impressive coalition of older voters, college-educated suburbanites and blue-collar workers.

"Trump and his team were depending on the Democrats either self-destructing or seriously wounding themselves," Sabato says. "That didn't happen. Democrats should be breathing a sigh of relief they didn't choose a 78-year-old socialist to be their nominee." Joe Biden has emerged as the Democratic Party's presumptive nominee. Credit:AP Biden's resurgence was driven by several factors – including his popularity with African-American voters and the belief he is the Democrats' most "electable" candidate. But the coronavirus outbreak has played to his strengths. Exit polls from this week's primaries showed voters overwhelmingly trusted Biden, rather than Sanders, to handle a major crisis. With Biden at the top of the ticket in November, Sabato says, the Democrats will be competitive in such states as Florida, North Carolina and Arizona, which would have been out of reach for Sanders.