In Rudy's case I don't see an evolution on this one. He embraces his former positions. You're correct that while reasonable, hate that word, regulation may be a state issue, the federal role is protecting the broad constitutional right of the individual to bear arms. As mayor, if he can get away with handgun bans and the like, I'd oppose him, but recognize that what he does in NY might not effect me. But now he's bringing that mindset to the national stage. Abusive firearms regulation is not the right of the states, even if the have large urban populations.
I think it's Blackwater, Inc. that proves that individuals do have their own armies.
I don't think it makes sense to allow a state to trump a constitutional right. Therefore, I must have explained myself poorly. New York should NOT be able to impose gun laws that restrict 2d amendment rights.