The first full year of the biggest vaccination drive in American history has saved many lives but has left many behind. The COVID-19 vaccines have proven incredibly safe and wildly effective, and many hoped they would bring an end to the crisis. But a year later, too many Americans remain unvaccinated and too many are dying. The vaccines’ first year has been rocky with the disappointment of breakthrough infections, the political strife over mandates and, now, worries about whether the mutant omicron will evade protection. Yet many experts say history will record COVID-19 vaccines as an extraordinary achievement that prevented tens of thousands of deaths.