President Joe Biden in a Tuesday afternoon speech insisted that Americans should not panic over the spread of the Omicron COVID-19 variant. “This is not March 2020 … we’re prepared. We know more,” Biden said. “I know you’re tired … I know you’re frustrated,” he said, adding that “this is a critical moment.” The federal government, he said, will set up additional COVID-19 free testing sites, starting in New York City. Biden also said his administration will purchase 500 million at-home rapid tests and deliver them by mail starting in January for free. “I know some Americans are wondering if you can safely celebrate the holidays with your family and friends. The answer is yes, you can, if you and those who celebrate are vaccinated,” Biden added, although a federal health official said Omicron can break through antibodies from initial COVID-19 vaccines. “Particularly if you’ve gotten your booster shot.” So …