Reuters: An “excessive exuberance” for expansion in the U.S. nuclear power industry has calmed because of the global credit and economic crisis, the head of the U.S. Nuclear Regulatory Commission said on Tuesday. Separately, a GE Hitachi Nuclear Energy official warned that the lack of credit will slow the pace of U.S. nuclear power development. U.S. Nuclear Regulatory Commission Chairman Dale Klein said in the past two years he worried whether there would be enough NRC staff to review …