Because when the shit comes to shove and the global economy takes a nosedive or your previous friendly third world manufactures give you the finger, having a "service industry" is worth nothing, but being able to produce the actual shit your businesses design and sell/export, matters.
Of course for the US this might be less so, because they can always force, by diplomacy or might, those developing world manufacturers to comply.
Another question would be why are people like the author of the article not particularly hot for manufacturing?
Because they are upper middle class pundits, have worked all their lives in the culture/media/academic etc industries, and could not care less for lost manufacturing jobs and other such stuff.
That's how we get books about the world being flat, industry doesn't matter, it's all "information" and "creativity" now, from people that could not suffer a day without electricity (and the hard work that goes into producing it), or without their car, etc.