The US government at this time had been reaching out to NK diplomatically time and time again but NK response has been that of firing and testing missiles and developing nuclear war heads to the point where the US had to go to the UN to deploy economic sanctions against Kim J Un to compel NK to stop -And what is the very first thing NK does after they have nuclear ICBM? To verbally threaten the US with them and to proclaim that they will make the US pay 1000x for their sanction actions.
What should have the US done instead of making it clear to NK that they will be blown off the face of the map should they fail to stop threatening the US with their new nuclear toys?