Our emissions standards on diesels requires a lot of additional equipment, diesel particulate filters, urea injection etc etc and normally have lower output/higher consumption. More complexity with this stuff, variable geometry turbos, high pressure fuel pumps and poor diesel lubricity all mean less reliability and higher maintenance costs. Our diesel is also generally more expensive than regular gasoline. Spending an extra $5-7k on a Diesel engine is hard to justify unless there is a very large increase in economy AND performance, and one intends to keep the car for a long time.
In short, it sort of becomes a novelty to have a diesel here unless you're towing a lot with a big truck, unfortunately. I love diesels but the EPA is killing them. That and the automakers are making more fuel efficient gasoline engines with turbos and direct injection with lower cost. We have a 2010 VW golf turbo diesel and its been a great car, now with 45k miles. Just oil and filter changes, fuel filter changes and tires, great power, easily makes 42mpg at 70-80 mph. But it also wasn't terribly expensive at around $23 well equipped. I'd love to have a turbo diesel in my Wrangler (I say MY wrangler because I probably won't buy another one based on overall quality and cost), but I would have to make sense with a substantial MPG and drivability improvement without a $5-7k price tag.