Paul Krugman still can't grasp why years of stupid investments cause inevitable recessions.

Krugman denounces Arnold Kling's quasi-Austrian explanation of why busts occur. The reigning Nobel laureate proceeds to triumphantly zing Kling with what he thinks is a killer question:

And now as then, the whole notion falls apart when you ask why, say, a housing boom — which requires shifting resources into housing — doesn’t produce the same kind of unemployment as a housing bust that shifts resources out of housing.

Yes, that's what Dr. Krugman wrote: Why doesn't a housing boom cause the same kind of unemployment as a housing bust?

A commenter named Scott replies:

You don’t create unemployment by hiring people.

Seriously, Paul basically just asked “Why doesn’t hiring people create the same unemployment that firing does?”

And people take him seriously?