PK: The thing about Japan, as with all of these cases, is how much people claim to know what happened, without having any evidence. What we do know is that recessions normally end everywhere because the monetary authority cuts interest rates a lot, and that gets things moving. And what we know in Japan was that eventually they cut their interest rates to zero and that wasn't enough. And, so far, although we made the cuts faster than they did and cut them all the way to zero, it isn't enough. We've hit that lower bound the same as they did. Now, everything after that is more or less speculation.
For example, were the problems with the Japanese banks the core problem? There are some stories about credit rationing, but they are not overwhelming. Certainly, when we look at the Japanese recovery, there was not a great surge of business investment. There was primarily a surge of exports. But was fixing the banks central to export growth?
In their case, the problems had a lot to do with demography. That made them a natural capital exporter, from older savers, and also made it harder for them to have enough demand. They also had one hell of a bubble in the 1980s and the wreckage left behind by that bubble - in their case a highly leveraged corporate sector - was and is a drag on the economy.
The size of the shock to our systems is going to be much bigger than what happened to Japan in the 1990s. They never had a freefall in their economy - a period when GDP declined by 3%, 4%. It is by no means clear that the underlying differences in the structure of the situation are significant. What we do know is that the zero bound is real. We know that there are situations in which ordinary monetary policy loses all traction. And we know that we're in one now.