Helicopter Drop Time: Paul Krugman Gets One Wrong

He writes:

Nobody Understands The Liquidity Trap: [W:]hen you have bought so much debt and created so much money that [short-term safe nominal:] rates are near zero, the public is saturated with liquidity; from that point on, they’re holding money simply as a store of value, which makes it no different from bonds — and hence a perfect substitute for bonds. And at that point further open-market operations do nothing — they just swap one zero-interest asset for another, with no effect on...