His options are complicated. State governments have locked down 169 million Americans in varying stay-at-home orders. Every day, Vice-President Mike Pence has brandished the one-page guidelines for the 15 days, urging compliance with hand washing and physical distancing.

A new mail out to millions of Americans titled «President Trump’s Coronavirus Guidelines for America,» arrived in mailboxes just before the weekend.

Trump hopes for economic resurrection

Yet President Trump has, for a week now, been peddling the idea of allowing more freedoms, hoping for an economic resurrection, with the country «raring to go by Easter.» That statement set off red alarms among health care experts who strongly urge strict adherence for a longer period.

This weekend the White House’s coronavirus task force will present the president with «a range of recommendations and guidance for going forward,» said Dr. Deborah Birx, one of the team leaders.

One strategy is to identify if areas in the U.S. that have fewer cases could open up first — the theory being that America could be divided into low, medium and high-risk areas.

«We may take large sections of our country that aren’t so seriously affected and we may do it that way, but we’ve got to start the process pretty soon,» President Trump repeated at a briefing Thursday.

States with fewer confirmed cases, like North and South Dakota, Nebraska, Wyoming, Montana and New Mexico and pockets in the northeast could be targeted as lower risk, while places like New York, with nearly half the reported cases, and other hot spots in urban areas, would be higher risk.

On Saturday, Trump said he was considering putting sections of New York and New Jersey into quarantine. It was not clear how he would be able to block road, air and sea travel out of a region that serves as the economic engine of the eastern United States, accounting for 12 per cent of GDP.

By Saturday night he’d retreated from that plan, saying the CDC would instead urge a strong travel advisory to hard-hit areas, and that «a quarantine will not be necessary.»

«I think we can start by opening up certain parts of the country, you know, the farm belt, certain parts of the Midwest, other places,» Trump said.

But the job of defending that decision, were it to happen, falls to his coronavirus response team working round the clock to get more data.

«What we’re trying to do is to utilize a laser-focused approach rather than a generic horizontal approach. And I think in the 21st century we should be able to get to that,» said Birx, who co-ordinates the White House’s coronavirus response team.

«The president’s made it clear that, in his words, he wants to open up the country. But we’re going to do that responsibly,» she added.

Muddling the public health message

After declaring himself a «wartime president,» the president appeared impatient this week with the economic casualties, including 3.2 million unemployed, cratering growth and a kick to a stock market that was soaring just a month ago.

Friday, he seemed to lean toward public health advice, telling a briefing, «life and safety and then the economy.»

But health professionals and state officials are deeply worried he will muddle the public health messaging.

«I am quite concerned that we’re considering these measures, especially when the science doesn’t support it,» says Nadia Abuelezam, an Infectious disease epidemiologist and assistant professor at Boston College’s Cornell School of Nursing.

«Evenif we do see a reduction in the number of cases, that doesn’t mean that it can’t resurge there, or it can’t be reintroduced to that particular area.»

It’s not at all clear how some states with fewer cases could open up, while neighbouring states with a higher incidence remain locked down. Confusion over what’s allowed where could prompt people to pay less heed to the restrictions, health experts fear.

«Viruses do not respect borders. Viruses do not discriminate. Viruses just want to find another body where they can replicate. And I think that’s something to really keep in mind,» says Abuelezam.

Infectious disease experts want more time to measure if the mitigation efforts across the country are working. They also want to better understand how many Americans have or had the virus, with few or no symptoms. That data would help more accurately define how much coronavirus is circulating in the community, but capturing that picture is still extremely complicated and will take time.

«I understand the concept — we’re hearing of ‘pockets’ [of coronavirus]. But the problem with those pockets is we don’t know if those are places where the disease just hasn’t spread, or testing hasn’t started,» said Dr. William Jaquis, president of the American College of Emergency Physicians, in an interview with CBC News.

«Look, we all had low cases at one time, right? And then Seattle started, then New York started, New Orleans, now Detroit, and California is ramping up.»

Modelling the new virus and predicting its effect on large populations is challenging, and changing, but data from more tests will ultimately produce a clearer picture.

«It’s really important to remember that the modelling results, the mathematical modelling results that are coming out about the United States, are all indicating that if we let up on the [physical] distancing now, we will see a large spike in the number of new cases,» says Abuelezam.

The coronavirus team at the White House is collecting as much data as fast as it can to provide concrete evidence to persuade an unpredictable president, who has a habit of freelancing from the podium.

Birx’s role at the daily briefings is to balance the bad news piling up as the cases mount and the slope of the virus goes straight up, with no levelling off.

You know, it’s one thing to have it. It’s another thing to die– Donald Trump, U.S. president

«Nineteen out of 50 states that had early cases have persistently low level of cases, at this point less than 200 cases [on Thursday]. So that’s almost 40 per cent of the country with extraordinarily low numbers, and they are testing,» said Birx.

«Models are models. We are adapting; there is enough data now of the real experience with the coronavirus on the ground to really make these predictions much more sound,» she said.

President Trump has seemed persuaded the number of deaths does not justify shutting down the whole of the country for longer than a few weeks.

«In my opinion, the mortality rate, it’s way, way down, and that takes a lot of fear out. You know, it’s one thing to have it. It’s another thing to die,» he said.

«When I first got involved, I was being told numbers that were much, much higher than the number seems to be. That’s one of the reasons I say, look, we’re going to beat this and we’re going to get back to work.»

Practically, Trump does not have the powers to regulate whether businesses open or close; the U.S. states can independently decide which restrictions will apply under broader federal guidelines.

On Friday, one of those lower-risk states, Wyoming, extended its closures of schools and some businesses to April 17. «It’s clear how important it is for us to take sustained action,» said Governor Mark Gordon.

With the U.S. now eclipsing cases in all other countries, the experience on the ground changes by the hour and the health-care response in some hard-hit areas is severely strained.

Nurses and doctors say they can’t get enough personal protective equipment; ventilators now being raced into production may not come soon enough. States are competing with each other to procure supplies.

The number of cases is one marker, but the rate of growth or the ‘cadence’ is even more telling, said Jaquis. In New York, cases doubled in three days.

Doctors say they need more time to allow them to respond to what’s about to hit, without worrying about the second rotation of spread.

«We’re not quite ready to take care of what’s coming. And we need to make sure that all of our patients and our communities and our health-care workers are protected. So right now, we need people to continue to stay home and we need to flatten that curve; they just need to continue with this for longer,» Jaquis said.

President Trump, calling himself a «wartime president,» travelled Saturday to Norfolk, Virginia, «to kiss goodbye» to the USNS Comfort, a naval hospital ship, headed for New York harbour to deal with the pandemic.

«It sends a great signal,» Trump said, «when the president is able to go there and say thank you.»

Perhaps a confusing signal for the millions of Americans under orders to stay at home.