Although I would love to see Land Rover, Toyota and many others bring diesel motors into the US, I would suggest you don't hold your breath. Here are a few reasons "IMHO" you will not see this happen anytime soon. First, you need to pass emissions in all 50 states. California is a real PITA and was the reason Land Rover did not bring in the 300 tdi in the mid 90's . Second, and biggest is MOST US drivers do not want diesels, period! Especially woman who influence most vehicle purchases. Like me, you are a very small minority. Most drivers want V6,V8 gas motors. VW is a good example to look at, yes they bring in Diesel cars but it is a total token boutique offering. They may have one on their lot if you are lucky but if you want anything special be ready to wait. They can sell every diesel car they produce outside the US. They don't care if they sell a single one here. It's a PITA to them. They do it simply for marketing. I'm sorry to say but you are preaching to the choir my friend. If you want a diesel they are available. Just completed a 1995 Discovery 1 conversion. Not the easiest but done and very happy with the results. Sorry to be such a downer.
All the best