House keys, wallet or purse, mobile phone and .... oh, yes: face mask.
Reluctantly for many, but also inexorably in the face of a deadly invisible enemy, small rectangles of flimsy yet live-saving tissue have in mere months joined the list of don't-leave-home-without-them items for billions around the world.
Not since humans invented shoes or underwear has a single item of dress caught on so widely and quickly from Melbourne to Mexico City, Beijing to Bordeaux, spanning borders, cultures, generations and sexes with almost the same Earth-shaking speed as the coronavirus.
"There has, perhaps, never been such a rapid and dramatic change in global human behaviour," says Jeremy Howard, co-founder of #Masks4All, a pro-mask lobbying group.
"Humanity should be patting itself on the back." But rarely, also maybe never, has anything else worn by humans sparked such furious discord and politicking, most notably in the United States.
Did anyone on an American beach ever pull a gun on someone for wearing a bikini, as an unmasked man did on a masked shopper this month at a Florida Walmart? As such, like other human habits, the mask has become a mirror on humanity.
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