There is written in the end:

But to invoke the unit root thing to disparage growth forecasts now involves more than a bit of deliberate obtuseness. How can you fail to acknowledge that there's huge slack capacity in the economy right now? And yes, we can expect fast growth if and when that capacity comes back into use.

And what I say is, that this capacity isn't there or at least not fully, because it is not capacity in producing the things, that are demanded in the future.

Der Amerikaner ist die Orchidee unter den Menschen
Volker Pispers