In addition to the problems with costs and motorized drivers wanting to force bicyclists off the road, you can look at past history.


A few years ago I was flipping through the Adventure Cyclist archives and ran across an article gushing about the idea of a bicycle path network. Something like 25 years ago (maybe 30 years ago now), the author was hopeful for a 40,000 mile bike path network. Just checked the USBRS page and they claim 12,000 miles have been marked (some of them, if not most, on roads that were built and are maintained for motorized vehicles).


Further, what are you going to do if there's not a bicycle interstate where you want to go? By the time you've completed this dream, Faux News will be screaming about wasteful spending, and 2/3 of the population will believe a cyclist doesn't belong on the road. How far are you going to drive to take your bike to the path you can ride?


All of which adds up to: unless you want to eliminate most of the cycling as done today, you don't want to go down this rabbit hole.