Remember last summer? Wales being Wales, rather than England, and having different laws, we all went about with our faces happily uncovered while the Saes sweated under their masks.

Now, it’s the other way round. This summer’s visitors to Wales are greeted by actual Welsh Government adverts (though you could be excused for thinking them a malicious prank) showing a Welsh flag, a smiling sun and the smuggest, most passive-aggressive slogan recently committed to paper or pixel. “No mask, no Wales.” Wales, it reminds us, isn’t England and our laws are different. 

The poster has made Coronazis and Welsh Nats (a Venn diagram of which would be a near-perfect circle) very happy. While not quite as much fun as putting up hand-scrawled signs saying “go home rats” like the Gogs did last Easter, it does carry the heartening imprimatur of being officially sanctioned, so as to give the impression that everyone in Wales thinks visitors need to be scolded like children.

If going unmasked last summer was a dreadful mistake that exposed us all to the most appalling risk, we’ve yet to her the Welsh Government take responsibility and apologise for it. Obviously, Wales isn’t England and our science is different, but a cynic might conclude that being different from England is the whole point in itself, and that Mark Drakeford’s elaborate game of grandmother’s footsteps –normally following what Boris does, two weeks later– has more to do with votes than viruses.

However cynical the Welsh Government’s strategy, it seems popular. For the foreseeable future, Wales will have to stay masked up in most indoor settings. Most Welsh people approve of this. So what’s the problem? If it’s not much hassle to wear one, and it keeps everyone safe, why complain? 

Two broad fallacies exist around masks. First, that most masks are effective in significantly reducing transmission of Covid-19.

Last summer’s experience in Wales didn’t provide much evidence of that. At the start of the pandemic, the Government’s scientific advisors thought face masks weren’t much cop, and the effort involved in enforcing them wasn’t worth the hassle.

On the former point, the scientists weren’t wrong. And that was at a time when it was generally assumed that Covid spread largely through droplets and contaminated surfaces, rather than –as is now acknowledged– aerosol transmission. 

Masks will stop most droplets, and muffle a cough or sneeze. If you’re coughing and sneezing, it’s not a bad idea to wear one. If you’re not, and you’re just out and about performing normal human respiratory functions, any Covid you’ve got is getting out and about too –more or less unhindered by masks– in the form of aerosols, rather than great gobs of mucus and phlegm. 

These aerosols are tiny. Typically around 100 nanometres across. Most masks are full of holes that are a thousand times bigger than that. Trying to stop aerosol particles escaping with the junk masks most people wear (either the ubiquitous blue paper ones, or the pretty folds of fabric that more fashion-conscious Coronazis are fond of) is like trying to avoid a hailstorm by holding sheep wire over your head. Or imagine it this way: If an aerosol virus particle were the size of a football, each of the thousands of small holes in your junk mask is bigger, by analogy, than a Type 45 Destroyer. This is why they’re not much cop.

The other misconception is that if masks weren’t any use, the Government wouldn’t make us wear them. 

If the purpose of wearing masks was to have a significant role in reducing the spread of Covid-19, that might be right. But it’s not. The idea behind compulsory mask-wearing is principally behavioural. It is to make people act differently towards each other; a warning that every other person is a threat, whether or not that’s true. They are a visual virtue-signal of obedience to the Coronavirus regulations, however irrational or destructive those rules might be.

And if junk masks themselves are inherently pretty useless, the way they are worn and handled makes them an outright liability. You probably take them off and put them on with soiled hands, stuffing them in a pocket when not in use. You probably use and re-use the same junk mask for days or weeks. If you have touched something that was contaminated with the Covid, voilà the most direct route to get the bug straight up your nose.

You can, of course protect yourself with a mask. It just has to be a proper one, manufactured to FFP2 (96% protection) or ideally FFP3 (99% protection) standards. But these cost much more than junk masks, there aren’t enough of them to go round and enforcing a law that ordered you to wear one would be impracticable. If you’re personally vulnerable to Covid-19, stock up on them, wear them as you’re supposed to and change your mask regularly. Then, there should be very little likelihood of your catching the Coronavirus, and no need at all for you to moan at other people for choosing not to wear one. 

With the continent sealed off by Covid, we will be welcoming a lot of English tourists in Wales this summer, and making a lot of money from them. Moaning and pontificating at visitors about masks does nothing to protect anyone from the Coronavirus, and still less to encourage them to come back.