Mask normalization

Kate Fassett, left, and Rachel O’Doud-Vega, masked and chatting at Mt. Tabor Park in Portland, Ore., on April 29. Some Americans are now considering a behavior scarcely seen in the U.S. but long a fixture in other cultures: routinely wearing a mask when displaying symptoms of a common cold or the flu, even in a future in which COVID-19 isn’t a primary concern.