Have to make sure we got the launch sites. Contrary to popular belief, nukes are not all destroying weapons. Annihilating an entire country is difficult.
And we would have to be sure that the Norks have not smuggled in bombs or concealed them off our coast.
“The U.S. governments 2017 report identifies a Russian ground-launched intermediate-range ballistic missile 3N-14 that can potentially carry a nuclear warhead.”
Frankly, if the Russkies can hit Europe, let Europe defend themselves.