Many good engineers agree there could be deep innovations providing factor of two or better improvements in energy security/efficiency, safety and arterial capacity. These include:
1) dynamic ridesharing based on location aware cell phones and in-car devices, and social networking (e.g. picking riders who like the same radio stations)
2) vehicles that can hitch to form trains while moving
3) powered roads that intermittently propel and recharge electric cars
4) e-guideways for passenger vehicles and light freight that can provide 4-15 lanes of capacity using very little land (frequently elevated or in tunnels); the vehicles could be either captive to the guideway or "dualmode" with the ability to drive on surface streets also; operation could be very quiet or very fast (not both)
Whereas $9.5 billion - public funds - has been committed to the concept of a national High Speed Rail (HSR) system, only a few millions - private funds - have been committed to highly transformational concepts. HSR would be used by a few people, occasionally. The systems above could be used by nearly everybody, every day.
Support and fund R&D in 21st century technologies at levels commensurate with their potential.