On Monday, President Donald Trump promised that the White House would ease social distancing restrictions much sooner than epidemiologists say is necessary to prevent millions of Americans from dying.

During a coronavirus task force briefing at the White House on Monday night, Trump addressed a nation anxiously socially distancing and sheltering in place, and told them America will soon be open again for business. “It’s going to be sooner than people think,” he said. “The hardship will end; it will end soon. Our country wasn’t built to be shut down.”

The president’s apparent change of heart on a national Covid-19 containment strategy came exactly one week after he had helped to roll out a 15-day plan from the US Centers for Disease Control and Prevention to help slow further spread of the deadly respiratory disease. The guidelines advise people to stay home if they or someone in their household is sick or if they’re among the most vulnerable groups, including the elderly and those with underlying health conditions.

Trump also made his announcement on the same day that the CDC reported 18,185 new confirmed coronavirus infections, which now total just over 33,400 nationwide, with more than 400 deaths. The explosion of cases makes the US one of the worst-hit countries in the world, behind only China and Italy. But the nation’s faltering testing rollout means that those numbers likely represent just a fraction of the actual cases, and the worst is yet to come. On Monday, the World Health Organization’s director general warned that the global pandemic is, in fact, accelerating. It took 67 days to reach the first 100,000 cases globally, 11 days to get to 200,000, and just four days to get to 300,000.

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Against that dire backdrop, Trump spoke to a nearly empty room of reporters, each separated by three vacant seats—a same-day policy enacted after the White House Correspondents Association announced someone in the press pool was suspected of contracting the coronavirus. The 15-day period is set to end on March 30. At that time, Trump said, he will make a determination about whether to continue the restrictions or extend them further. When asked when he planned to end the stay-at-home orders, Trump declined to give a firm date. What he did say was, “I’m not looking at months, I can tell you right now.”

But many epidemiologists are saying that months of aggressive social distancing and self-isolation are exactly what is required to prevent a catastrophic loss of life. The US government has been recommending such measures on a national scale for only a week—which isn’t even long enough to have the data necessary to know if they’re having the desired effect. While public health experts say that at some point the US will have to figure out how to start relaxing some of these restrictions in a targeted way—to allow economies to come back online in places with low transmission rates—they stress that doing so will require the large-scale deployment of testing, community screening, and contact tracing. None of these are up and running yet in the US. Abandoning the blunter tools of social distancing now, without any of these systems in place, would be not just premature, they say, but disastrous.

“It would be utterly irresponsible to urge people to go back to work and normal social life,” says Larry Gostin, a professor of global health law at Georgetown University. “All the evidence suggests that if governments lift physical distancing too soon, it will cause a major resurgence of cases and deaths.”