The roughly 150 mph winds hopped over Chef Menteur Highway and blew out walls at a NASA assembly plant. By the time the tornado fizzled out over Lake Borgne, it had caused millions of dollars of damage. Together with a cluster of other windstorms, it yielded the seventh presidentially declared major disaster of 2017. States have come to rely on these declarations, a practice that helps individuals and communities recover from disasters. And since the 1980s, the federal government has been on the hook for the majority of recovery costs when a disaster is declared. But as the country faces an increasing number of billion-dollar disasters, federal officials are considering scaling back that spending, aiming to save taxpayer money and encourage states to prepare for disasters with their own resources.And that has some local officials worried. Without the federal relief they depend on, many communities could be hamstrung after a disaster, unable to help their most vulnerable residents.Some could have to hold back so much money that other programs and services would suffer, said Bryan Koon, Florida’s emergency management director. “They would be miserable places to live and if you have a large enough disaster, they would be destroyed.”The proposed pullback, along with the threat of more frequent and intense natural disasters linked to climate change, is already forcing cities and states to change the way they prepare for — and recover from — events like tornadoes, forest fires, floods and hurricanes.