Let me reflect on this from the viewpoint of balancing supply and demand of U.S. dollar-denominated financial assets at the macro level. The key phrase is "safe assets." Financial intermediaries perform an important function of investing in risky assets while issuing safe debt. Debt issued by private financial institutions, along with securities issued by governments, constitutes safe assets that are provided to the economy.
A prime example of such a function is the bank deposit. Through the results of recent research on safe assets, we are now aware of two empirical regularities over long periods.5 The first point is that the share of safe assets in the whole universe of financial assets including equities is more or less constant.