As Covid-19 vaccines become widely available in the United States — thank you to both the Trump and Biden administrations — we now face the fact that the virus is still spreading and many people don’t want to get vaccinated. Government won’t force them, but their bosses could.

Vaccine skeptics have lots of reasons — “developed too fast,” “side effects,” “don’t trust politicians and government ‘scientists’ pushing it,” etc. There are lots of well-intentioned messaging studies on how to overcome those reasons and lots of surveys saying “things are going in the right direction” — a recent one found only 24 percent are still saying “No way, ever.” But there’s also lots of quiet resistance. Folks who don’t want to get vaccinated don’t want to talk about it. They don’t want to be lectured to. (And they may even not admit it to pollsters.)

Getting to Yes (Needs More Than Preaching)

The federal government’s responses have been a combination of preaching and free giveaways. A few weeks ago, the president added one more: vaccinations were already free, but now employers who let their employees get vaccinated also get tax credits to pay for the lost time on the job. That’s on top of public service announcements, endorsements from celebrities and an infinite number of appearances from Dr. Fauci. These are all admirable efforts, and, by comparison with other nations, the United States is doing well.

But is it enough? Do we really think we’ll get to herd immunity, or even a manageable threat, if more than 20 percent of adults and their children can still carry the virus? Will we have to do more?

The obvious approach is the one we apply in our schools for the usual childhood diseases from measles to polio: require vaccination with the usual exceptions for health and religious objections.

But sadly, today’s U.S. is so polarized that almost no one is even seriously discussing it. There are many who argue that vaccination “is a personal decision” and that no one should be required to submit to the jab. This ignores the fact that the consequences of each personal decision can affect thousands of other people. We don’t let people personally decide to drive cars without licenses or seatbelts (or after three beers) or to build what they want on their own land without zoning approval. However, even discussing a vaccination requirement seems taboo.

Carrots Not Sticks

As an alternative, my Brookings colleague Robert Litan suggested going beyond making it free: he proposed cash payments. Governor Jim Justice of West Virginia took up the idea, offering a $100 savings bond to young people who get vaccinated. As a practical matter, though, a national program of vaccine bribery is unlikely to be sufficient, even if it were to get through Congress.

So is there any way to get to herd immunity besides preaching and praying? Yes.

Can Markets Work When Government Won’t?

It is settled law in most states that employers can require vaccination because they have the right (and sometimes the obligation) to set health and safety requirements for their workplaces. Writing for the Society for Human Resource Management, Allan Smith stated, “As Covid-19 vaccines become available, many employers will have a strong case for requiring employee vaccinations, so long as their vaccination policies have certain exceptions, are job-related, and are consistent with business necessity.” Some health care companies have already required their staff to vaccinate. But what about everyone else?

Why would employers do this? Perhaps because it would preserve the health of their other employees and their families and make it easier to attract new hires. Perhaps because being able to tell your customers that everyone inside is vaccinated might bring them back more quickly. Or perhaps because it’s the fastest way to stop having to wear masks.

Of course, knowing they can require vaccination doesn’t mean that all employers, or even most, will choose to. Nonetheless, action by even a third of U.S. businesses would, by my estimate, lead to vaccination of an additional 12 million adults and get the vaccine rate over 80 percent.

So what would it take? The U.S. Department of Labor should spell out clearly how employers can require vaccination to protect their workers while complying with federal law. (The Department of Labor’s emergency Covid-19 rules are in process and already overdue, but the agency has produced many regulatory safe harbors in the past and could add this without much delay.)

Although the right of employers to require vaccination is clear, there are some exceptions. The Americans with Disabilities Act requires employees with allergies or other disabilities that prevent vaccination be offered accommodations such as remote work if doing so would not impose an “undue hardship” on the employer. Title VII of the Civil Rights Act discourages requiring vaccinating those who object due to “sincerely held religious belief, practice or observance,” but this applies only if honoring objections doesn’t impose “more than a de minimus cost or burden.” It’s also worth noting that where employees are protected by a union, a vaccine requirement would likely have to be negotiated.

How many people are covered by these exemptions? Very few. A survey of vaccine-skeptical health care workers conducted in December found that less than 3 percent mentioned either allergies or religious objections. The common objections to vaccination are not legal exemptions and won’t overcome an employer vaccination requirement.

Don’t Tread on Me

Covid-19 public health measures have unfortunately been politicized, but letting businesses themselves decide whether or not to require vaccination should be bipartisan: Republicans and those skeptical of government regulation should appreciate that individual businesses will make their own decisions based on their own needs. Democrats can look forward to millions of additional vaccinations.

Since the federal government will not regulate, it should try clarity about what it doesn’t regulate and let markets work. Private decisions by millions of employers, based on their own business needs, might convert the unwilling. The result of these “invisible hands” could be both safer workplaces and a quicker path to a post-pandemic America.