Frustrated by the sluggishness and inconsistencies of state regulation, 135 insurance companies, agencies, banks and financial services trade groups urged Congress yesterday to establish a federal regulator for the insurance industry. In a letter to Senators Richard C. Shelby, the chairman of the Senate Banking Committee, and Paul S. Sarbanes, the ranking Democrat on the panel, the insurers and bankers complained of the burden of having to comply with regulators in 50 states, saying it was a very costly system that "provides no advantage to the consumer." The shortcomings of state regulation have been underscored in the last year by...