Here are a few, and as I come across more I'll post them. One of the biggest roadblocks is all the infrastructure upgrades have to be implemented simultaneously, power generation, storage capacity, distribution/transmission and delivery on a national level. Try designing and building a new high voltage transmission line through multiple states. I'd be willing to wager the approval process with all the jurisdictions involved would take years or decades. These lines aren't your Granddad's transmission systems, these are higher voltage lines requiring a wider right of way with much larger electro magnetic fields (try convincing people along the right of way the increase EM won't be detrimental to their health). Just one of many legal/permitting battles even before any work can begin.
If you work hard and have a skill set to match success and wealth is yours for the taking