The Korean Peninsula conflict is different. The US keeps soldiers there to make sure that any conflict started by N. Korea is also an explicit attack on the US.

The Korean Peninsula conflict is different. The US keeps soldiers there to make sure that any conflict started by N. Korea is also an explicit attack on the US. So nuking US soldiers would likely mean getting nuked in return. On a side note, this agreement is likely all that keeps S. Korea, Japan, and Taiwan from deploying their own nuclear weapons.