Bank of Japan Governor Haruhiko Kuroda stunned investors today by announcing a big expansion of the central bank's bond-buying program. The move won't fix Japan's ailing economy by itself, but it might help, and Kuroda is right to try. The U.S. Federal Reserve likes to signal its intentions and avoid taking financial markets by surprise. Kuroda prefers shock and awe. Investors were wrong-footed by the scale of the BOJ's quantitative easing when it was first announced last year. Now Kuroda has ambushed them again. Few expected the scale of purchases to be ramped up so soon -- to 80 trillion yen a year ($724 billion), ... (full story)