The U.S. death toll from COVID-19 topped 600,000 on Tuesday, even as the vaccination drive has drastically brought down daily cases and fatalities and allowed the country to emerge from the gloom and look forward to summer. The number of lives lost, as recorded by Johns Hopkins University, is greater than the population of Baltimore or Milwaukee. It is about equal to the number of Americans who died of cancer in 2019. Worldwide, the COVID-19 death toll stands at about 3.8 million.