In the latest sad setback for environmentalists in the battle over corporate average fuel economy (CAFE) standards, the U.S. National Highway Traffic Safety Administration decided Friday not to increase fuel-efficiency requirements for 2004-model-year pickup trucks, minivans, and sport-utility vehicles. Last year, Congress voted to lift a six-year-old, industry-backed ban that prevented NHTSA from examining fuel-efficiency standards for the light trucks. The decision not to increase such standards was a blow to environmentalists, who argued that boosting the standards would be critical to protecting natural systems and national security alike. The current standard requires light trucks to average 20.7 miles per gallon. Helping to lead the fight to toughen CAFE standards is Sen. John Kerry (D-Mass.), who wants to tie mpg performance to tax breaks for automakers. Kerry also supports tax credits for consumers who buy hybrid vehicles.