Since NK missiles can reach US homeland, no one believes that Washington would trade LA or San Francisco for Seoul. The nuclear umbrella has become full of holes.
Therefore 70% of South Korean population is for arming with nuclear weapons. SK will go nuclear in the next 2 decades IMO and Japan will follow suit.
Cannot come soon enough. I hope this century, Taiwan, Philippines, Vietnam and Indonesia also get them.
Whether they declare openly or not, that is up to them....but the payback w.r.t CCP geopolitical decision to proliferate will inevitably return with interest this century.
ROK Navy has made some excellent decisions regarding its submarine development. Very well done.