Originally Posted by DVPGSR
Actually because our interstate highway system was originally designed to support troop movements...
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The federal government footed the first 90% to construct the roads. Now it is left up to the state governements to maintain, however there is no federal standards of maintenence and many rodas and bridges are in dire need of repair or updating. A standard for the states to confirm to would be good but tough to enforce. A better idea is to follow what the Europeans do and nationalize the interstate system and charge a yearly per-car tax to drive on the roads so each car needs a sticker to drive on the highways. That money would then be used to maintain the roads.
You raise another good point: there are specific taxes that go to Autobahn maintainance. Unlike here when they say "your tax dollars at work" when there is construction and you wonder what part of your taxes it is and where it goes. As far as that's concerned, for the record, the standard asphalt/concrete thickness on the Autobahn is 26", and if the slightest crack is detected, the entire section of road is replaced. In the U.S., roads can vary from 10-15" in thickness, and you're lucky if the DOT fills the chuck holes in at all. Not to mention, German roads tend to last twice as long as American roads.