In the aftermath of the identification of the Omicron variant in the United States, President Biden extended a mask requirement on buses, trains and airplanes through mid-March and offered insurance reimbursement for at-home coronavirus tests, along with better access to those tests for people without insurance. Dr. Anthony S. Fauci, the president’s top medical adviser, exhorted Americans to take advantage of vaccines.“We have 60 million people in this country who are not vaccinated who are eligible to be vaccinated,” Dr. Fauci said. “Let’s get them vaccinated. Let’s get the people vaccinated, boosted. Let’s get the children vaccinated.”In California, that was the message, too. At a news conference in the Central Valley, where the virus has raged amid persistent vaccine resistance, Mr. Newsom said he did not expect to reinstate shelter-in-place orders or classroom closures, although the state planned to increase coronavirus testing at airports among travelers from countries designated by the Centers for Disease Control and Prevention.Much still depends on the actions of individual Californians, he said: whether they heed his repeated, urgent calls to get vaccinations or booster shots, for instance, and whether they take other precautions, like adhering to mask mandates.“It’s important for folks to understand we have agency,” the governor said. “People have been thriving with these vaccines.”In San Francisco, as word spread of the discovery of the Omicron variant among its residents, many were less “thriving” than resigned to the measures that have become a literal way of life in the city. Before the variant showed up, the city had been engaged in a robust public chiding of the mayor, who had been caught on Instagram on an indoor dance floor without a mask.Edlyn Kloefkorn, who has an 85-year-old mother at home on dialysis and a fifth grader who had just gotten his second dose of vaccine on Sunday, wondered whether her family’s life would ever return to their old normal.