A week after disaster, doubts about Japanese government’s grip on crisisTOKYO — Reeling from a historic earthquake and tsunami, Japanese authorities struggled Saturday to deal with a humanitarian crisis, a still-untamed nuclear power plant and emerging doubts about the government's credibility and competency. Across the Pacific, trace amounts of the radioactive isotope xenon-133 lit up a sensitive detector in Sacramento, and scientists said it was likely from the crip
