No one yet knows whether the Omicron variant of COVID-19 will be devastating or no big deal. On the “no big deal” side, there’s not currently evidence that it makes people sicker than previous strains, so it’s possible that it will simply wash over a global population rich in COVID antibodies. On the “potentially devastating” side, the Omicron variant seems to feature an especially large number of mutations, including some that scientists worry make it more likely than earlier strains to evade the COVID-19 vaccine. The Biden Administration’s line so far has been that Omicron is a “cause for concern, not a cause for panic.” Its first policy intervention, developed last weekend, while the President was on Nantucket for Thanksgiving, was to ban travel from eight countries in southern Africa, where the strain was first identified. On Tuesday evening, the Centers for Disease Control and Prevention announced new testing requirements for inbound international travellers. “Here’s what it does: it gives us time,” Biden said, in a speech explaining the policy. Among its overseas allies, the United States was on common ground. The United Kingdom adopted a similar policy. Japan, which has been more restrictive since the start of the pandemic, simply banned all international arrivals, sealing itself off.