Pretend you wanted to drive 8000 miles. The IRS expects that the cost per mile allowance is $0.50 based on gas, oil, tires, vehicle depreciation.
To drive those 8000 miles the apportioned cost would be $4,000. You can get 10 round-trip tickets London-NY off-season and 5 on-season for that.
During your trip if you follow your manufacturer's recommendations you'd need to change your oil three times. So would everyone else. At equal intervals. What a pile up at the mechanic at 3000m, 6000m, and just past it. Yuck!
If you have average street tires then the trip there and back would kill half your tires (so they only have half left on them you need to replace them on this trip).
If the speed limit was set at 100MPH and there were no stops you'd actually maintain that, but given that you will stop to stretch your legs, etc. that average goes down to about 80. That's 100 hours of driving, which with two drivers and sleeping in the car is 5 solid days. What's the value of 10-man-days lost?
Finally even if all those things were true, the largest cargo that could be transported is a triple-tractor trailer -- 3 containers. This ship can do 18,400 http://en.wikipedia.org/wiki/M.... You'd need 6,133 trucks to equal that and it would take them 5 days. The cargo ship can make it in 3-4.
This is a nonstarter from every possible fiscal angle for the end-users, even if the road magically arrived today.*
* note that I didn't address at all that by the time your European car reached the US, it would not be homologated for street use by the DOT so you'd need to rent a car here anyway, and vice versa.