Future U.S. Bicycle Infrastructure

How is it possible that I've entirely missed out on the conversation that has been in the works for (from what I can find) the last six years regarding a U.S. interstate bicycle system? I had no idea that such infrastructure was currently in the works, but am fascinated to learn more about this project.

Proposed map of US interstate bicycle route
*Image obtained from adventurecycling.org

The idea of being able to hop on a bicycle and have a means of more easily traveling from state to state, or even within my own state is highly exciting to me. The routes, apparently, will be supported by each states' Department of Transportation. Why it's taken the U.S. so long to figure out that this would be very useful and monetarily beneficial to the economy, I cannot determine, but for anyone interested and/or who, like me, has been left in the dark regarding this subject, there are some interesting articles to read here and here.

While I'm interested in this project and highly excited about the prospect, I'm a bit disappointed that it's been in the works for over six years (according to Bike Portland) and there's still nothing definitive in the works. It's so upsetting to see all the discussion and not have the actual work in progress. Wouldn't it be great to see this come about in the next few years? I'd love to know more of a timeline for completion if anyone has any information out there.