A Proper Broadcasting Network
..is not that difficult to implement. If done perfectly, every major switiching station has it's broadcasting server which will serve all the major streams for the DSL lines attached to this switching station.
And these servers will get their data from a hierarchy of servers that culminates at the stream source. You could stream an HD video to every single DSL line of a complete country (including the US) this way and it would probably take much less bandwith-miles than the current youtube traffic.
To some degree this already exists in the form of Video-On-Demand networks run by the big telcos.