The first known unknown is the virus. Most economic forecasters are assuming that the Omicron wave, like the Delta wave, will recede before too long, leaving behind little lasting damage to the economy. “Omicron could slow economic reopening, but we expect only a modest drag on service spending because domestic virus-control policy and economic activity have become significantly less sensitive to virus spread,” the economic team at Goldman Sachs said, in unveiling its 2022 predictions. That assessment could well turn out to be accurate—let’s hope it is—but it’s too soon to say. Over the weekend, the seven-day average of new covid cases set a record of more than four hundred thousand. Since Christmas Eve, bad weather and Omicron have caused the cancellation of more than fifteen thousand commercial flights. In the last week of December, the number of people eating at restaurants was about thirty per cent below the same period last year, according to data from OpenTable.

Even if the U.S. economy does get through the Omicron wave relatively unscathed, with few or no lockdowns, the new variant could affect production in the Chinese economy, which supplies many components and finished goods to the U.S. China just recorded the largest number of weekly cases since suppressing the initial wave of the pandemic. The spread of Omicron represents the biggest challenge yet to Beijing’s “zero covid” policy. A decision to lock down large parts of China’s economy could exacerbate problems in the supply chain. In a globalized economy, no country—even one as big and powerful as the U.S.—exists in isolation.

The second big known unknown is economic policy in Washington.