Sadly the american appetite for diesel in a passenger car aplication was killed when Oldsmobile produced the 5.7 diesel. The engine itself was underpowered, and it did not have a water seperator in the fuel system, so injection pumps and blown headgaskets where a common issue.
You can buy a diesel car here, but the market just dosent seem to want it yet (ewww, diesel is nasty)
IIRC, The Jeep Liberty had a diesel option, and it got scrapped due to poor sales. I would love to see the big 3 figure out how to make a decent diesel compact pickup. Something in the 3L to 4L displacement would be nice, and should have no problem hitting 30 MPG and be able to actually tow something. (VW used to have something like this, was worthless for towing, but got 45MPG and could haul something in the bed)
Also, with Diesel still averaging a dollar more a gallon, people are hesitant to buy, even if it is still cheaper per mile due to the increased fuel economy, the initial price of the diesel scares people away.