WASHINGTON — President Biden’s aggressive move to expand the number of vaccinated Americans and halt the spread of the Delta variant is not just an effort to save lives. It is also an attempt to counter the continuing and evolving threat that the virus poses to the economy.Delta’s rise has been fueled in part by the inability of Mr. Biden and his administration to persuade millions of vaccine-refusing Americans to inoculate themselves against the virus. That has created another problem: a drag on the economic recovery. Real-time gauges of restaurant visits, airline travel and other services show consumers …
