And Fedex's success depended far more on aviation advances than on the Interstate Highway System. Aviation that was pushed by private industry (while also enjoying support from the militaries of the world).
In the US, the major "infrastructure" type projects that were government driven are often listed as the Erie Canal, the Hoover Dam, and the IHS. Some will throw in the TVS as well, though I consider that more of a state-cooperative effort. Yet we still seemed to have a great deal of scientific progress that in turn led to economic progress before these huge programs were enacted.
The steam engine, the locomotive, the airplane, wireless radio, etc. etc. Goddard didn't have much government support in his initial efforts yet was a pioneer.
I'm not discounting that governments can have a disproportionate impact on some programs. But do we really want to have a government that picks winners and losers as we currently do with alternative energy? I guess we'll find out on Tuesday.