Moody's cuts Japan rating, blames politics By Rie Ishiguro | Reuters TOKYO (Reuters) - Moody's Investors Service cut its rating on Japan's government debt by one notch to Aa3 on Wednesday, blaming a build-up of debt since the 2009 global recession and revolving-door political leadership that has hampered effective economic strategies. Japan is preparing to elect its sixth leader in five years to replace unpopular Prime Minister Naoto Kan, under fire for his handling of the response to a March tsunami and subsequent radiation crisis at a crippled nuclear power plant. The downgrade, while not out of the blue, served...