The initial strike on the North Korean Regime could be from a few obvious things:
- Immense Troop build near the 33rd Parralel
- North Korean Artillery pointing their guns at the South Korea on key areas of infrastructure power plants, water plants, telecommunication area or centers
- Another ICBM test by the North Koreans
- Threats of hitting the US except the language has intent to really hit the US unlike provocative North Korean Propaganda
- North Korean Patrol Boats seizing commercial ships who are in or near their waters
These 5 points could start an initial strike by the US.
Whom could launch a Initial Strike, I personally think North Koreans would kick off the initial strike caused by a "broken arrow". I say once a ICBM test missile goes past the 1st ring of ICBM test range, I think somehow if their intended target was a coordinate somewhere in the open ocean, something could happen and could land somewhere else. Meaning either someone else got a hold on the missile through hacking, or their was a pre-planned launch coordinate someone forgot to erase but was left in the missile flight plan and that was the intended target.