According to orthodoxy, taking some starch out of the yen — an unofficial, yet unmistakable, goal of Prime Minister Shinzo Abe's signature monetary policy — is manna to exporters, who will help pull the country out of its protracted economic malaise.

But recent figures throw into question this traditional success strategy, upheld by many aides and advisers to Abe. The cheaper yen has so far failed to reverse the growing trade deficit, belying the myth that the economy can be sustained by exports.

February's trade deficit, released Wednesday, was ¥800.3 billion, the largest negative amount for the month since 1979, when comparable data became available.