My husband did that pocket-patting thing on the front and back of his shorts that men do to show they’re searching for something.

“No, I, um don’t carry it with me,” he told Francis Do, who wouldn’t let my husband order a banh mi until Do saw his covid-19 vaccination card.

Do pointed to the handmade sign that wrote out the new policy at his Fairfax restaurant and explained: “No card, no table inside. President Biden said people need to get vaccinated. And we don’t want covid in our restaurant.”

My husband grimaced. He’d really been craving a beef banh mi.

“I’m sorry,” Do said.

The owner of Pho, Banh Mi and Grill was taking a big gamble, knowing that a good portion of customers — business he was hurting for after laying off five people and closing indoor dining more than a year ago — wouldn’t have the card with them or would take umbrage at his demand.

My family and I have seen signs about wearing masks and keeping socially distant, but this is the first time we’d been asked to present an official Centers for Disease Control and Prevention vaccination card. (I have a mom bag, so of course I had my card with me — along with tissues, a sock, scissors and a concert program from three months ago).

My card allowed me entry to use the bathroom, but our otherwise cardless party was seated outside, banned from even touching the big menu. Do flipped the pages for my husband and son.

It’s the debate of the moment, from employers to concerts to news conferences. How far do we go in requiring proof of vaccination?

Some restaurants and bars in Los Angeles are closing again this month after seeing surges in of covid-19 caused by the highly contagious delta variant. In San Francisco, city officials are considering making vaccination cards a requirement for having a nosh and a sip.

There’s been a backlash. Eric Clapton said he wouldn’t perform at venues that require fans provide proof of vaccination.

And Rep. Marjorie Taylor Greene (R-Ga.) argued that her HIPAA rights were being violated when a CBS reporter asked her if she’d been vaccinated. (Her rights were not being violated. That would’ve been the case if a third party with knowledge of her medical records stepped in and answered the reporter’s question).

It’s legal for an employer to require the proof, and for Do to withhold a seat in his restaurant and a bowl of pho until he sees the CDC card.

“Freedom is for outside,” he said. “But if you come into my house, my restaurant, I can ask.”

We’re not out of the pandemic yet. That graph showing the Denali and Grand Teton peaks of coronavirus infections in December and April seemed to settle into flatlands until an uphill climb in recent weeks. And it’s mostly happening in states with low vaccination rates, like Florida, Arkansas, Missouri, Nevada and Louisiana.

But even in our blue, super-vaccinated region, new daily reported cases rose 86.4 percent in D.C., 61.5 percent in Virginia and 64.7 percent in Maryland over the past week.

It’s what everyone worried about when the CDC first relaxed masking and social distancing recommendations. The unvaccinated are mainstreaming, going maskless and hosting the virus’s giant mutation parties. And that’s causing rare but disturbing “breakthrough cases” — vaccinated folks who are nevertheless infected. And that has included members of Congress, White House staff and Olympic and professional athletes.

“We apologize for the inconvenience, but unfortunately we’ve had a breakthrough case of Covid-19 with one of our fully vaccinated staff members,” read an Instagram post by The Village Idiot restaurant in Los Angeles, which closed for several days for employee testing.

That’s one of the first things Do worried about — his vaccinated staff getting sick from vaccine deniers coming into his restaurant, maskless, pretending they are vaccinated.

Without an association or union or government ruling mandating the vaccine proof requirement, it’s a bold and brave move for a struggling business owner.

I asked him how much business he has lost.

“I’d say 25 to 30 percent,” Do said.

And then he lost some more.

“Dude, why would I carry my card with me?” one surly young man asked when Do explained the policy.

Do pantomimed a camera.

“Maybe you took a picture of your card? A picture is good,” he said.

But nope, Cardless and his crew left.

I watched this happen several times on a Sunday afternoon, and the numbers were about right. For every three parties that sat outside or showed him a card and were seated indoors, one left. Some in disgust, arguing about the efficacy of the vaccine.

“I don’t understand that,” he later told me. “Medicine is part of society. These people go to the doctor when they are sick. They go to the hospital when they are sick. Why don’t they trust medicine now?”

Some, after they left grumbling, tapped out acidic, one-star reviews online for Do’s restaurant, which he opened in 2015 near the campus of George Mason University.

“I wish other businesses do it with me,” Do said. “I asked some other restaurant owners if they would do it. But they didn’t want to lose the business.”

Every time Do came to our table that day, he apologized again for keeping my family outdoors and explained how much he wants to help end the pandemic.

I had a lot of respect for his position, his resolve and his correct idea that social pressure is what will end the pandemic sooner.

It wasn’t easy to watch, especially because he seems to have a naturally brusque demeanor, which isn’t softened when the ever-present mask hides his wide smile.

As far as he knows, he’s the only restaurant in Northern Virginia requiring a CDC card.

“I did it after I saw President Biden on TV,” he told me. “He’s so frustrated. He wants people to take it seriously. And I believe if I lose a little now, we will be successful later. We will all be open and healthy.”

Twitter: @petulad

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