Remember like a decade ago,?? ?? ??? when it was trendy to use the term FOMO? It was everywhere; everyone had it.Well, I think we could use a heavy dose of fear of missing out for the vaccine-hesitant in 2021.

While it might be a corny acronym now, FOMO remains a strong tool — and one I wish the U.S. took advantage of more to get shots in arms.

Consider the Canadian government, which announced Friday it intends to make vaccination against COVID required for all commercial air travelers, as well as travelers on trains between provinces, and all cruise ship passengers. France, another nation with high vaccine availability, will also mandate vaccination for cross-country plane, train, or bus rides.

Neither the U.S. government nor U.S. airlines, meanwhile, have mandated vaccines for air travelers and I wish they'd do atleast that. There are hurdles to doing this — to name a couple: blowback from certain customers and FDA technicalities — but it is doable down the line.

The rash of viral videos of anti-makers getting kicked off planes is one reason to move towards a vaccine requirement to fly. So many flight attendants spend their days begging folks to wear masks, risking assault from unruly anti-mask passengers. Take this out of their hands. The staunch anti-mask, anti-vax Venn diagram is pretty much a circle, so mandating vaccines would save lots of hardworking airline employees a lot of trouble. Fewer anti-maskers would hold up flights if they couldn't get on the plane in the first place without a vaccine. Granted, all air travelers, even the vaccinated ones, might have to still wear masks for the foreseeable future. As public health experts have said, it's not either or. We have to use all the tools at our disposal to combat COVID.

The highly transmissible Delta variant is also a powerful argument for requiring passenger vaccination and mask wearing. The days of empty middle seats have largely come to an end. As airlines pack planes again, there is a risk someone near you can transmit COVID with a sneeze or a cough, even if they are fully vaccinated. Being vaccinated continues to protect against death and the need for hospitalization, but rare breakthrough cases have shown some vaccinated people can pass the disease onto others or suffer flu-like symptoms themselves.

This Tweet is currently unavailable. It might be loading or has been removed.

This Tweet is currently unavailable. It might be loading or has been removed.

Some airlines, like United Airlines, Hawaiian Airlines, and Frontier Airlines, are already requiring employees to be vaccinated as air travel in the U.S. creeps toward pre-pandemic levels. With travel, restaurants, and venues inching toward normal capacity, FOMO is a powerful tool and making life — making fun, making vacations — inconvenient for the unvaccinated may well be more effective than repeatedly preaching (correctly) that vaccines save lives. If you're required to be vaccinated to go indoors, to go on flights, to go to work, and to attend college (perhaps eventually school too as the vaccine becomes available to more children), the ability to skip a shot becomes more and more difficult.

The idea that the jab protects you from severe COVID outcomes is somewhat abstract. It requires folks to imagine themselves and loved ones suffering. Many people cannot, or will not, do that. Missing a trip with friends, however, is immediate. It is concrete. Simply put, it sucks and creates FOMO. Yes, it's like withholding dessert from a child who won't eat their peas. But that strategy is a classic with kids for a simple reason: It works. I'd imagine lots of folks who "did their own research" — e.g. read dumb Facebook posts — would forget that "research" the second they might have to skip a bachelor party in Nashville because the airline required a vaccine.

Now for some important caveats. The U.S. is in a unique position where airlines, or the government, could reasonably mandate vaccines for air travel eventually, especially once the vaccines move beyond emergency authorization and get full FDA approval (that's what some airline execs say is partially holding them back). There are also billions of people globally who would love the opportunity to get vaccinated but don't have access. So many nations have precious little supply as the U.S. begs people to get the vax. Many international travelers likely couldn't be held to the same standard as U.S. travelers because they simply haven't had the chance to get vaccinated. (FYI: If you want to help the global vaccine effort, Mashable has you covered.)

Full FDA approval is expected to come as soon as September, which would then make it more palatable for airlines (or the government) to mandate vaccines for travel. That means the U.S. could work on a similar timeline as Canada, which plans to put the mandate into effect in the fall per its own country's regulations.

That timeline also leaves room for the vaccine push to continue. Following fears stoked by the Delta variant, more Americans have been inspired to get the COVID jab. Vaccination rates in the U.S. have jumped recently after weeks of lagging numbers. But public health officials are still working on outreach in communities with low vaccination rates. There are folks not getting vaccinated because they fell down a rabbit hole of misinformation. But unvaccinated people are also more likely to have lower incomes or be wary of medical racism. They may not have childcare or the ability to take off work to get a shot or deal with the temporary side effects. We have to reach and support those folks.

There's some evidence already that vax mandates have been effective. This CNBC article quotes peoples who got vaccinated because they wanted to travel to places with restrictions. Sixty percent of people got vaccinated because they wanted "to visit family or friends but not being able to without a vaccine," according to a Time/Harris poll of about 1000 adults taken in March. Fifty-two percent said they were influenced by "wanting to travel but not being able to without a vaccine." Travel is clearly a major way to motivate people to get vaxxed. Imagine if you had to do it to fly anywhere in the U.S.? No flying off to Disney. No jetting to the Super Bowl. No soaring through the sky to your family for Christmas.

Moreover, a strong majority of Americans want a mandate for air travel. A new Harris poll of about 2,000 Americans from last week found 64 percent of respondents wanted a vaccine passport to be required to fly.

Jetting around the country is not a right. It's a privilege. If you're signing up to fly in a tin can, sharing a confined space with dozens of other people, then asking you to get jabbed isn't a bridge too far. What's more, I'd like to see more, for lack of a better word, non-essential places require vaccination. If the NFL, concert venues, college football conferences, chain restaurants, and major gym brands required vaccination, hell, we'd see skyrocketing vax rates.

For now, I'm hoping we can start with air travel. It might be corny to say these days, but FOMO works. Let's put it to use.