If any policymaker is thanking his lucky stars over Donald Trump's victory, it's Bank of Japan Gov. Haruhiko Kuroda.
The yen's plunge since the U.S. president-elect shocked the world on Nov. 8 gave Abenomics a second wind. November was the worst month since 1995 for a currency that has fallen 11 percent since the last time the Bank of Japan board met. Already, surveys show a marked bump in business sentiment, raising hopes that 2017 will be a year of the kind of wage increases Prime Minister Shinzo Abe has tried to produce since 2012. Hence, the BOJ's decision Tuesday to leave monetary policy unchanged.
There are two problems with this sudden burst of optimism. One, it ignores the fact Trump is 30 days away from taking office, and no one knows what he really plans for the U.S. economy. Two, the yen's trajectory may convince Abe that his work to restructure Japan is done.