Dear President Trump,

I have not been one of your supporters, but when it comes to combating the coronavirus, saving lives and getting as many Americans back to work as quickly as possible, I am praying for your success, because so much is riding on the decisions that you, and only you, can make. So what I am about to say is truly in the spirit of being constructive: You need a plan.

And here is what is also obvious: There is a high degree of agreement among leading public health experts on the contours of what could become a three-step “Trump plan.”

By embracing their strategic approach as your own and sticking by it — not going off on tangents every day in your White House briefings — you would deliver what the public craves most in the short run: the confidence that we actually have a plan to fight this virus, save everyone we can and rapidly reopen the economy based on science and data.

Let me explain.

What is eating away most at all the people sheltering at home today are these questions: Am I safe? Are my kids safe? Will I get paid again? Will my savings last, if I have any? When will my children get back to school? When am I realistically going to be able to get back to work? Will my workplace be shut forever?

And what is eating away at every shop owner, small-business manager, multinational C.E.O., banker, investor and entrepreneur are these questions: When can I realistically expect to get my business back up and running? Where and when do I redeploy my workers or scarce capital? Who do I lay off and who do I hold onto?

That the stock market bounces back because of a trillion-dollar bailout does not relieve their anxiety.

Only an end to this crisis and a vaccine will totally relieve their anxiety. But what would give everyone a boost, from Main Street to Wall Street to the management suite — and buy the patience we need — is if they saw that you had a clearly defined, multiphase plan for combating the coronavirus based on science.

That is, a plan that starts with sheltering in place today and pivots to gradual openings and back-to-work opportunities as soon as the data tells us that is safe — with your experts giving regular updates on where the country is in achieving benchmarks laid out by this plan.

People want to know that you have a plan and are acting off it. Right now they think you have hunches and moods.

In hopes of stimulating a discussion about a plan, Dr. David Katz, a public health expert, I and others last weekend helped to spark a debate about how we best maximize our nation’s two necessities: that is, limiting the number of infections and deaths from the coronavirus, and simultaneously maximizing the speed at which we can safely fold workers back into the workplace, based on the best data and expert advice.

That is a plan for what Katz called “total harm minimization,” because while people can die from the virus, they can also die from depression, anxiety and addictions that flow from having their jobs, savings and futures crushed by an economy in permanent lockdown.

As Tom Frieden, a former director of the Centers for Disease Control and Prevention, wrote in The Washington Post on Wednesday: “The choice is not between health and economics but about optimizing the public health response to save lives while minimizing economic harm.”

In all honesty, though, sir, you immediately and crudely jumped into that discussion with a tweet last Sunday night — “WE CANNOT LET THE CURE BE WORSE THAN THE PROBLEM ITSELF” — that polarized and caricatured the whole debate. Your critics accused you of only caring about the stock market, not human lives. Meanwhile your supporters accused your critics of moral preening and ignoring how many people would die from a deep and prolonged economic depression.

We must do better. To be sure, we need an immediate all-out push by states and the federal government to get hospitals the equipment they need to deal with a surge of coronavirus patients, an effort that is at long last underway. But beyond that, you need to articulate the three-step plan that is out there and is yours for the taking.

Step 1: First, you need to call for a 50-state sheltering-in-place/social-distancing program. While the experts differ on how long that national lockdown should be — two weeks, four weeks, eight weeks, whatever the C.D.C. recommends, I say — they virtually all agree that it is needed to manifestly slow the spread of the coronavirus, to prevent our hospitals from being overwhelmed and to buy us the critical time we need to collect the data required to inform all future decision-making.

As the public health expert Ezekiel Emanuel, vice provost for global initiatives and a professor at the University of Pennsylvania, wrote in this newspaper on Monday, you need to “immediately order the closing of all schools and nonessential businesses and impose a shelter-in-place policy for the entire country. The majority of the population is already experiencing some version of this protocol or feeling the effects economically; we need to standardize these protocols for the full public health impact.”

We cannot have Florida and Nebraska more open while New York and New Orleans are more closed, but with undiagnosed infected people still moving between the two. You have to use your bully pulpit to stop that. The more you slow the spread everywhere, the more time for needed hospital equipment to arrive and new treatments to emerge.

If you have not seen them, check out the widely referenced graphs in an analysis on medium.com titled “Coronavirus: The Hammer and the Dance” by the engineer-entrepreneur Thomas Pueyo.

“Strong coronavirus measures today should only last a few weeks, there shouldn’t be a big peak of infections afterwards, and it can all be done for a reasonable cost to society, saving millions of lives along the way,” Pueyo wrote. “If we don’t take these measures, tens of millions will be infected, many will die, along with anybody else that requires intensive care, because the health care system will have collapsed. … Every single day we delay the coronavirus, we can get better prepared.”

I realize, Mr. President, that some of your Republican “red state” governors and rural mayors are telling you not to ask them to shelter in place, because their less densely populated states have not been that affected. But they are doing you and their citizens no favors.

As my Minnesota friend Michael T. Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, pointed out to me, this virus hits large metro areas first, because of their density and global connections — and many of those are in “blue states.”

“But this virus will find everyone,” he told me. “It may start in the cities, but I can tell you that it is going to hit central Minnesota. Don’t be on the wrong side of this. This is all of us against the virus, not red states versus blue states. And if we all don’t act now, one day it will just be one big fire” of infection.

Step 2: We use this period of lockdown to gather as much data as possible about who has the coronavirus, where they live, what their ages and degrees of illness are, what the mortality rate is at what ages, and what other ailments or immune deficiencies they may have.

Right now we keep reading that more young people in their 20s are dying from it than expected. But if we don’t have a picture of the total number of people infected, that anecdotal evidence could be dangerously misleading. One city or hospital system may tell you that out of 500 cases of people under age 25 treated, 50 people died. But suppose the number of infections in that region for people under 25 is discovered through testing and data collection to be 25,000 — the picture looks totally different.

Step 3: This data can then be the foundation of what Katz calls “the pivot.” Once we have slowed the transmission of the coronavirus nationally — and developed a stratified national risk map — we can then, on the basis of that data, said Katz, begin phasing people back into the workplace to get the economy humming again.

The truth is, said Osterholm, we’re going to have to begin to venture out more and more, even if the data shows that these lockdowns have not flattened the curve. “Someone has to collect the garbage, deliver the foods and medicines, and keep basic services running, no matter what,” he explained. “We are going to have to learn to live with this virus to some degree, until there is a vaccine — no matter what the data shows. Otherwise, there is no economy.”

But ideally, if the data does indicate suppression, Osterholm added, we can begin to figure out exactly who has had the virus and become immune, who has gone more than two weeks without manifesting symptoms and in which areas, and then come up with different levels of reintegration into the economy. This would also allow us to devote more energy “to protecting our front-line health care workers” and those most vulnerable to being killed by the coronavirus — the elderly, those with weakened immune systems and other vulnerable groups.

By letting the epidemiological data drive that pivot, Mr. President, you will reassure people that your pronouncements are based on science and the strategic logic of a plan, and you will be able to bring the whole country, not just your base, along with you.

Your presidency and our immediate future are inextricably intertwined. You need to rise above what sustained you during your first three years — dividing, misleading and impugning experts and the deep state — and give the country what it so desperately needs and craves now: a science-based plan.