That's the question that Japan Post Bank Co., the banking unit of Japan Post Holdings, has been grappling with. Its answer: buy and hold over half a trillion dollars, or $577 billion to be precise, worth of foreign corporate bonds. That, as Bloomberg notes, is "more than the investment-grade portfolio at Fidelity Investments or the fixed-income holdings at Britain's Standard Life Aberdeen Plc." And since Japan Post is a public company, majority-owned by the government, it means that one Japanese bank (really, Japan, due to its state-ownership)  is directly funding countless US-based corporations, resulting in hundreds of billions in stock buybacks , and this bank is also indirectly funding the hiring of thousands of US workers. In this "new normal" era of super low rates, this represents a major change from just a decade ago, when the foreign bond portfolio at Japan Post Bank was virtually nil.