The necessity of insurance – home, health, auto – is about as certain as death and taxes. So insurance companies play an important and non-negotiable role in our lives. Except when they choose not to. Sometimes they decide to get out of insurance arenas that don’t meet their standards of risk assessment; when they do, the federal government picks up the slack – as they have with flood insurance, crop insurance and lately, terrorism insurance.

And sometimes they simply decide to walk. That’s what Allstate is doing with property insurance in the Southeast. Florida no longer stands nearly alone in losing insurance coverage because of the risk of hurricanes. Allstate Insurance has added coastal regions of North and South Carolina, Alabama, Maryland and Virginia to the growing list of areas nationwide where it is cutting back homeowners insurance coverage.

Allstate, the nation’s second-largest home and auto insurer behind State Farm, confirmed Thursday that it is dropping coverage for about 12,000 homeowners in eight counties of South Carolina, 4,000 in 14 counties of North Carolina and an unspecified number in Alabama. Allstate will no longer write new homeowners’ policies starting in 2007 in 11 coastal counties of Maryland and 19 in Virginia, although existing policies will be renewed.

Collectively, the changes leave Allstate with sharply reduced coverage for almost the entire eastern seaboard. The insurer announced several weeks ago that it will no longer offer new property insurance policies, including homeowners’ in Connecticut, Delaware and New Jersey beginning next year. It said earlier that it was dropping coverage to 120,000 customers in Florida and eight downstate New York counties, along with 26,000 Texas policyholders for wind damage, and also limited homeowners’ coverage in coastal areas of Texas, Louisiana and Mississippi.

Chairman and Chief Executive Edward Liddy has said the company is forced to cut its exposure to disaster-related losses. While shifting its emphasis to other areas, such as financial services, Allstate has been seeking the creation of a government fund to help cover homeowners’ losses in major disasters.

Allstate is engaged in skimming the property insurance portfolio they want, and looking for government coverage for the rest. That’s the history of the industry and calls for a new definition of risk analysis as it applies to the industry profiteers that will, for instance, insure your car but not your house.