As an American journalist working in Moscow, Paul Klebnikov, accumulated a lengthy list of enemies, ranging from Chechen mobsters to billionaire bandits. Those responsible for his murder last year may not have realized just how many allies Klebnikov also had. A team of top-flight investigative reporters from America and Russia has committed itself to untangling the case of Klebnikov, the 41-year-old editor of Forbes Russia who was gunned down at the peak of his career while walking home from his offices in northeastern Moscow on the evening of July 9.