As a libertarian with a localist bent this is a issue I think a lot about. But if America wants a Nanny State....lets go full Nanny State where the Nanny can be fired if the kids go to the ER with a yard dart sticking out the side of little marys head.
If government worked as promised once a area becomes known as a slide, avalanche, wildfire, tusnami, tornado, sinkhole, earthquake or flood risk where the chance of total loss of the property or the occupants is a real number, permitting of new residences and major external improvements needs to stop immediately and insurance switches to high risk private insurance within the decade (or post bond equal to the value of your property).
Commercial property know are owned by people who know how to manage risk. (man I sound like a 1%er) The average citizen has no idea of the risks of home ownership until FEMA is tagging their house with spray paint. This will be beneficial to all of us who built and live in sensible locations and FEMA will have funds for the real freak events. (Johnstown Flood, Texas City, Dust Storm that swallows Phoenix, Yellowstone Super volcano, New Madrid) The plains and Midwest land in flood plains is for farming as it is most fertile and cheapest for the purpose and the risk is only a few thousand dollars per square km. Land near the seas is great habitat for birds and multiuse use parks. .
If a developer wants to attempt to improve area to mitigate the risk he can set a bond in perpetuity to pay for the losses on the high risk community and make the cost of the land closer to the true cost for the community. Corrective action may be attempted by developers but they are taking on future risk not the local, state and federal government. New Orleans, Florida, the foothills of LA, Sandy point, Martha's Vinyard and thousands of miles of coastlines will all still have there risky homes to buy but will be clearly a risky buy with not only high insurance premium but a declining value. Building on the side of a mountain or hill without rebar cemented into bedrock needs to be in the building code. Redlines will be back and drawn by Geologists, Mortgage Companies and Insurance Companies.