Our countrymen. Largely confined to their homes and worried about the spread of the coronavirus and its risks to their own health or that of loved ones, a segment of the United States has turned informant, calling the police, public health authorities and the employers of people they believe are violating social-distancing decrees or stay-at-home orders. Across the country, these complaints have led to shutdowns of dog groomers and massage parlors as well as citations and police scoldings to restaurant and bar owners whose patrons are lingering too close to one another. The police in Laredo,...