Thanks, still this is not federal issue but state-based, that is beautify of federalism.
When the state enacts laws that violate the US Constitution and the civil rights of those under the jurisdiction of the US, the only redress is the courts. If some resident alien who lives in Oklahoma were to apply for an OK SDA license and subsequently were to be denied for not being a citizen, they would have definite grounds to file a lawsuit in Federal court. I think they would win. Especially since KY already lost this same argument, as was noted above.