SIR - George Bush has explicitly acknowledged that global warming is real and human activities are contributing to the problem ("Better than Kyoto", June 25). That is progress of sorts, but the president is holding stubbornly to his position that greenhouse gas emissions can be reduced without setting standards and timetables for measuring performance - a curious stance for someone who holds an MBA degree. His classroom work at Harvard Business School should have taught him that any enterprise must set targets if it's going to deliver anything of value. Mr. Bush should review his textbooks, then develop a meaningful climate policy that sets measurable benchmarks for reducing greenhouse-gas emissions.