Construction Spending: Not Good News At All

I tried to get excited about the latest news, focusing on non-residential construction.  (No hope any time soon for residential activity.)  Here's the private non-res data:
Const NR
We've got a couple of months of gains there; grounds for happy talk, right?   I poked around the detail and found one sub-sector driving the recent increases:  manufacturing.  Huh?  Manufacturing has been pretty hard hit by the recession, so I look at the history (courtesy of 

Const Mfg

The data suggest that either 1) construction of new factories is totally impervious to the recession, or 2) the time lags are so long that we have not yet seen the downturn, but it's coming.  Guess which hypothesis makes more sense to me?

Conclusion: look for manufacturing construction to start a slide soon, and for that slide to last a couple of years at least.