If you take seriously even the most moderate global warming predictions, you have a moral obligation to oppose spending more money trying to redevelop New Orleans’ lowlands and a moral obligation to oppose those trying to coax low income families into moving back there.

Most of the Earth’s surface is below sea level and, in fact, is covered by ocean. Only 30 percent of the Earth’s surface is dry land. On the dry portion, there are several areas that actually lie below the level of the ocean. These low-lying areas remain dry land only because they are separated from the ocean by higher elevations. Three of the more famous of these areas are the Dead Sea, Death Valley, and New Orleans. Of those three, only New Orleans is adjacent to the ocean. A large portion of New Orleans is below sea level. That area is part of New Orleans and not part of the seabed only by virtue of massive levees built and maintained by the U.S. Army Corps of Engineers at a cost of billions of federal taxpayer dollars. The levees are designed to withstand up to a Category 3 hurricane; they could be improved to resist up to a Category 4 or even a Category 5 hurricane, but at the cost of additional billions of dollars and only after decades of effort. Key words in the foregoing description are “up to”; Hurricane Katrina, which caused so much damage in 2005, had weakened to a Category 3 hurricane by the time it made landfall on the Gulf Coast, the level “up to” which the levees were designed to withstand, but the levees broke anyway.

A modest rise in sea level of only one or two feet, as predicted by the United Nations Intergovernmental Panel on Climate Change, would virtually guarantee that another Category 3 hurricane will overwhelm the New Orleans levee system and flood the sunken areas again.

In addition to being an increasingly and inevitably ineffective barrier to reinvasion by the sea, the levee system creates two additional problems. The first should be of grave concern to anyone who cares about the environment in general and the ecology of the central Gulf Coast in particular. The levees interfere with the flow and, consequently, with the silt and nutrient transport system of the Mississippi River. Prior to the construction of the levees, the river had built up an extensive delta consisting of an enormous system of wetlands extending from New Orleans to the sea and for hundreds of miles along the Gulf Coast on either side. With the flow disrupted by the levees, deprived of the sediment and materials needed for maintenance and growth, the wetlands are shrinking and subsiding, actually sinking into the sea. This process is exacerbated and accelerated by any rise in sea level.

Not only are these disappearing wetlands ecologically valuable in their own right as rich havens of biological diversity for marine, terrestrial, and arboreal life, they also serve as natural barriers to storm surges all along the Louisiana and Mississippi coasts. Thus, the wetlands help protect not only New Orleans, but scores of communities along the Gulf Coast. These communities rely on the wetlands to dissipate storm surges along the coast—they are not protected by the extravagant levees surrounding New Orleans. As the wetlands subside and the sea rises, this protective barrier disappears. Thus, the futile attempt to save a portion of New Orleans dooms dozens of communities and thousands of mostly poor people along the Gulf Coast.

If that were not bad enough, there is an even more insidious, more morally reprehensible consequence caused by the levee system and the development it is meant to facilitate. No rational person who had a choice in the matter would voluntarily live below sea level in proximity to the ocean, levee or no levee. It is Russian roulette, Atlantian style. But the real estate is understandably cheap. Accordingly, low income families are herded into government housing and shotgun shacks in the high-risk areas. That is as cynical, as immoral, as racist a policy as could be devised in modern America. It effectively barters the lives of New Orleans’ poor, i.e., black, population for tax dollars and federal subsidies.

Virtually all of those displaced from New Orleans have moved to places like Houston, Dallas, and Baton Rouge—places with larger and more vibrant, more dynamic economies than New Orleans had at its peak. Better jobs, better schools, better housing, less crime, and better neighborhoods are available at their new homes. Many of them lost much of their personal possessions, but in terms of their living conditions, they are much better off—returning to New Orleans will not restore their possessions. Call it the Moses Red Sea Plan: lure undesirables into an area below sea level and let nature take its course. It works great, unless, of course, you are the Egyptians. When the consequences of an action are predictably disastrous, good intentions are irrelevant. We may wish to help those who survived Hurricane Katrina, but placing them back into harm’s way is the antithesis of the help they need.