Re: "just gabbing on until..Norks have the ability to nuke the whole US and..free to invade SK.
Obviously their army hasn't been tested in a long time, but then neither has the North's.
South Korea has had more recent military experience than North Korea. For example, most of the South Korean Marines spent a lot of time in Vietnam, and Ho's boys learned real fast to NOT attack the ROK Marines. They basically only left because the US pulled the rug out from under them, they wanted to hang around and kill Commies en masse. https://en.wikipedia.org/wiki/2nd_Marine_Division_(South_Korea) https://forums.anandtech.com/threads/so-what-kindve-atrocities-did-s-korean-marines-do-to-vietnamese-people-in-the-vietnam-war.1765979/page-2
You really, really, REALLY don't want to get the ROK Marines mad at you. You really don't.