Ragged U.S. and Puerto Rican flags fly on a roof in Yabucoa on May 16, eight months after Hurricane Maria struck. Many in the Puerto Rican town are still without power. (Carlos Giusti/AP)

A NEW report by independent public-health researchers estimates that at least 4,645 people died as a result of Hurricane Maria in Puerto Rico. Consider that number. Contrast it with those who died from Katrina (almost 2,000) and those killed in the 9/11 attacks (almost 3,000). Remember President Trump’s visit to the stricken island in the storm’s aftermath, tossing out paper towels and telling Puerto Rican officials they should be “very proud” that hundreds didn’t die from Maria as in a “real catastrophe like Katrina.”

Think how many lives might have been saved if Puerto Rico’s devastation had been handled with the seriousness and urgency it deserved. Ask yourself whether Mr. Trump would have thought — or acted — differently if the American citizens who were affected had lived not in Puerto Rico but in Texas or Tennessee.

A study published Tuesday in the New England Journal of Medicine by scientists from the Harvard T.H. Chan School of Public Health and other institutions takes aim at the official government count of 64 dead. It suggests the actual number of deaths — many caused by interruption and delays in medical care — is more than 70 times higher than that reported by Puerto Rico officials. Researchers acknowledged their estimate, based on calculations from surveys of randomly chosen households, is imprecise and further study is needed. But the report, along with earlier reporting and analysis by the New York Times, paints a devastating picture of how people, particularly the elderly and infirm, were imperiled by long-standing losses of electricity, water and communications.

The power of a nearly Category 5 storm in causing damage cannot be overstated, and the fact that Puerto Rico is an island presented unique challenges. But neither local nor federal government rose to that challenge. Bad decisions by Puerto Rico officials were compounded by a federal bureaucracy that didn’t aggressively marshal the resources that were needed. Many communities were cut off from vital services for weeks and months. The Post’s Arelis R. Hernández and Laurie McGinley recounted how a 54-year-old woman contracted an infection and died Nov. 29 after lapses in medical services, including the 20 minutes her family had to wait to get cell reception just to call 911. “The worst part was knowing I could do nothing to help her,” said her daughter.

Even now, eight months after Maria slammed into Puerto Rico, parts of the island are still struggling; and with hurricane season about to start, there are concerns that Puerto Rico is ill-prepared to deal with new emergencies. “The situation is not over,” said Domingo J. Marqués, an associate professor of psychology at Albizu University San Juan, who helped conduct the Harvard study. Will more Americans have to die before their government wakes up to their needs?