Any vehicle marketed for the needs of the majority of Americans needs to be : capable of going 150 miles between refueling,reasonably safe and comfortable in all weather,and capable of normal highway speeds,i.e. 65 mph.
We already know how to build cars such as the Pontiac Vibe which get 35mpg .That car /van is comfortable ,practical,and cheap on gas. I have ridden in one from Cincinnati to Fort Wayne,and had no complaints.
But such vehicles are not "sexy" and are not advertised/sold with the effort put into other vehicles.
Americans(and others) have literally bought into the idea that one's vehicle can represent and supplement one's sex appeal,beauty,economic status,or phyical prowess.
As a nation we COULD be driving safe ,comfortable,reliable vehicles from the technology and cars available and sold the past several decades.But most of us chose cars based on emotion and advertising.We COULD be using significantly less fuel.We CHOSE otherwise.
I initially was in the market for the seatbelt but since I couldn't find one that didn't angle right across my throat, I settled for left elbow room and the kids chose it for the cup holders.