Answer: In general, the realists believes that there's not enough bang for the buck. It says the pace and scale of cuts required by Kyoto would hurt the U.S. economy without providing significant environmental benefits. USA believes more research is needed to understand the warming trend and how technology can be used to reverse or slow global warming.
Explanation: The United States hasn't become part of the agreement because it considers a problem the fact that several major developing nations, including India and China, are not required to reduce emissions under the agreement. China is expected to overtake the United States as the world's largest producer of greenhouse gases as early as this year.
Perhaps an even bigger problem with Kyoto, however, is that scientists say that even if it is successful, it would do relatively little to slow the pace of global warming.
