People wearing protective masks walk past closed shops on the the Coney Island boardwalk in Brooklyn, N.Y., April 11, 2020. (Caitlin Ochs/Reuters)

In the coming days and weeks this country will, God willing, see its COVID-19 epidemic begin to subside. Policymakers will have to decide how quickly to lift their social-distancing rules — and what to replace them with. Several groups of states are working on plans, and the Trump administration has released a sensible set of guidelines in which areas would reopen in three phases.

In setting such a policy, errors bring with them immense harms. Lifting the lockdowns without having other control measures in place would likely allow the virus to reassert itself; but extending the lockdowns too far would prompt a backlash (there are already signs of this) and further deepen the severe damage we have done to the economy. Therefore, we must develop alternatives to lockdowns as quickly as possible and implement them carefully.

Some necessary elements of such a plan are simple, obvious, and easy to achieve. Mask-wearing should be strongly encouraged, perhaps required, in public places where people cannot avoid coming close to each other. Lockdowns should be ended on a gradual schedule, with the least affected areas going first. And hard-hit regions should get their outbreaks under control — with consistently declining case loads, plus the testing and treatment capacity to handle a potential increase — before they reopen.

Even when businesses and schools do reopen, they should work to keep customers and students separated to the greatest degree practicable. Policymakers should also be mindful of the fact that the disease hits the elderly hard while overwhelmingly sparing children: Continuing to isolate the old while the young return to work and schools reopen will often make sense.

The administration’s guidelines showcase one way of putting these concepts together. Areas with control over their outbreaks and adequate health-care capacity would start by slowly reopening businesses with strict social-distancing rules in place; then proceed, in Phase II, to more relaxed rules and reopening schools; and conclude with Phase III, in which businesses are back in full swing and even members of vulnerable populations can go out and about with some precautions.

Other ways of attacking this problem, though, depend on technologies and capacities that do not yet exist. A drug to treat the worst cases of the disease would be a godsend, saving lives and reducing the risks of reopening. At this writing there are highly promising signs regarding remdesivir, but we need to be aggressively testing as many options as we can. A good treatment is our most likely route out of this mess.

It may also be possible to clear Americans to work by testing them, or even to roll out a truly massive testing effort to comprehensively track and control the disease’s spread — but only if we have far more tests than we are currently making. We need to light a fire under that process, both by shredding red tape and by providing big incentives to any business that can churn out tests.

Phone apps, meanwhile, may track users’ movements and alert them if they’ve come into contact with someone infected, making it far easier to detect new cases and quarantine them. These apps should be strongly encouraged and incentivized once they are available, even if for privacy reasons they should not be mandated.

None of these are groundbreaking or counterintuitive proposals. But we are distressingly far from being able to competently implement some of these measures. Let’s attack that problem with the ferociousness it demands.