Or what if New York decides to go along with the Real ID Act National ID card thing. Just picture this : You're from New Hampshire, you have a non-Real ID Act-complying New Hampshire driver's license, and you get pulled over in New York City. The cop asks for your license and registration. The cop notices that you have a NH license. He says, "I'm sorry, but this is an invalid driver's license." You say "How come?" The cop replies "We only recognize driver's licenses from Real ID Act-complying states as valid driver's licenses." Then all of a sudden the cops draws his pistol and points it at you, saying "You are under arrest for operating a motor vehicle in the State of New York without a valid operator's license." Then you're hauled to jail and your car is impounded.
Not gonna happen. Almost all states have a "reciprocal recognition" law. That is to say that if the driver's license of New Hampshire is not recognised in New York State, THEN the driver's license of New York is NOT recognised in New Hampshire.
This may possibly be a violation of the Interstate Commerce clause of the US Constitution, as well as the Lemuel Penn Ruling.
Either way, New York State looses that fight big time.