> 3. Banks can't simply accept cash from depositors and be done with it. They need to convert that cash into an asset of some kind. And right now, the asset of

> 3. Banks can't simply accept cash from depositors and be done with it. They need to convert that cash into an asset of some kind. And right now, the asset of choice is short term treasuries (exactly the thing in short supply). When interest rates are 0% there's nothing stopping them from doing this.