I don't like Thomas Friedman either. But, that is a good quote that I think Milton would agree with. He doesn't say that invention is a necessary condition for prosperity. He said it is a necessary condition for prosperity GROWTH.
I'm shocked that you inferred as much from his quote. He's notoriously vague (because he's not actually saying anything), and after re-reading the quote I'm not sure where you got the "growth" part from.