Terrible idea. A lot of people would take advantage of that in reckless ways. Plus our oil consumption would go up even more. If anything, maybe we should consider a national speed limit again.
No offense...but national speed is just a lazy way of trying to reduce consumption. Encourage smaller and more efficient cars..that makes a much bigger difference than forcing people to drive like snails.
A small Ford Fiesta driving at 90 mph surely uses less fuel than a Dodge Ram at 55.
Why not do both? It isn't as if we have to choose between speed limits and efficient cars. Personally I think a 60 mph national speed limit plus more efficient cars would be a good idea. No speed limits are not an option, especially in areas with significant populations.
Pretty much sums up my thoughts. I'd invest a lot in alternative energy, public transportation, etc. too though. Actually I'd say the real problem is our highly inefficient (and heavily subsidized) suburban lifestyle. I can understand wanting some space from downtown but there's no reason to have endless stretches of nothing where you literally can't survive without a car.