Has The Bank Of Japan Started Another Round Of Central Bank Wargames?

"Never pick a fight with a central bank. The only one who gets hurt is you. Unless, of course, you are another central bank."

"So it is not quite true that a currency-issuing central bank has no opponents. No-one in the private sector will oppose it, unless they have a deathwish. But other currency-issuing central banks might, if they perceive its actions as threatening to their own economies. "