To a greater degree than any other large segment of U.S. business, the housing industry depends for its health on a hefty and often erratic supply of credit. With good reason, many builders, lenders and manufacturers of building supplies blame Washington for the un even flow of mortgage money. And in last year's tight-money squeeze, they were so starved for funds that home-building fell to a nine-year low of 1,228,000 new nonfarm starts. Last week six major materials-making companies teamed up to try to reduce housing's dependence on federal credit and the vagaries of national economic policies.
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