President Joe Biden on Thursday announced a number of measures he hopes will help combat COVID-19 as his administration struggles to control the disease, but vowed not to try to force areas to lock down, after two cases of the virus variant Omicron were detected in the United States. Biden and his administration are extending the mask mandate on airplanes, trains, and public transportation into March 2022, helping launch hundreds of new vaccine clinics, and forcing all inbound international travelers to test negative for COVID-19 within one day of departure regardless of vaccination status or nationality. The president and his advisers are also ramping up marketing to try to convince all eligible Americans to get a booster shot, as more and more studies show COVID-19 vaccine effectiveness wanes over time. It’s all part of what the president described as a “battle plan to combat COVID-19 this winter.” The plan, Biden said, …