Whether and how much to credit industry for voluntary cutbacks in greenhouse gas emissions. That's the subject of reporter Jeffrey Ball's piece illustrating the "political tightrope walk" the Bush administration is walking on global warming. Some interests, for instance the free-market Competitive Enterprise Institute, are concerned about opening the door to regulating carbon dioxide emissions. They see the issue fracturing any would-be industry unanimity in opposition to eventual regulations. Others are concerned that without incentives, companies will have no reason to move ahead with voluntary emission cutbacks. Meanwhile, convinced of the eventual certainty that carbon dioxide emissions will be regulated under some future administration, some electric utilities continue their efforts to make plants more fuel-efficient and to establish emission offsets. "If they don't get something for their past efforts, what's the incentive going forward to continue those actions?" an Edison Electric Institute official asks. The administration, meanwhile, appears to be recalculating whether it has legal authority for the long-promised credits system. The Department of Energy is still weighing the issue, Ball reports.