The US market got a different set of DR/DRZ250's than the rest of the world. The DRZ250 here is totally different than the DR250S/SE that preceded it. The DRZ250 was also definitely not sold as road legal here. Bolting the parts on to make it legal would be easy of course using either factory parts from a different market or a baja kit. Most states won't technically allow such things and the VIN number is in the DMV's computer as not road legal making it difficult to get tags in many states. Some, like Colorado are more reasonable, others like CA wil make it nearly impossible.
If its a trail bike you want do take a look at a KDX200, its a very fine machine and 50lbs lighter than the DRZ250 :)