If threat of a nuclear response by the US failed, and North Korea decided to strike first, the best option would be to target North Korea’s mobile launchers and missile bases, Chun said. “Intercepting them in the air through multiple layers of missile-defense systems is the last resort available,” he said, adding that “massive retaliation” would continue until North Korea accepted unconditional surrender.
Naoko Aoki, an associate political scientist with the Rand Corp. in Washington said there were various ways Japan and South Korea could be doing more, such as contingency planning. If there was a military situation on the peninsula, Japan would need to find a way to evacuate its tens of thousands of nationals in South Korea, which would likely involve Seoul signing off on allowing in Japanese military planes for evacuations, she said.