I say to you because you stay in America for long time now you are too soft with Chinese. You speak as if you are American Japanese not Japanese. Situation is grim here when concern with security.
I read your post you seem to not like Uyoku Dantai you know it is Uyoku who defend Japanese interest and say what many don't want to say .
Beware not to be liberal Nihonjin1051, careful not to listen to too many Chinese. Remember Japanese First. Everything else second.
Well we have to analyze the possible causes for the lapse in coast guard monitoring. Remember the 2013 Sewol Ferry incident in South Korea? Well you do know that that was the pretext used by Seoul to disband the South Korean Coast Guard, right? Yes, they literally do not have a Coast Guard at all right now. The ones conducting inderdiction duties is the ROKN , which poses quite a host of problems when it comes to necessary intervention measures. Probably this is the reason for the lapse in Seoul's abilities to interdict.
Please review:
South Korea Parliament Approves Plans To Disband Coast Guard After Ferry Disaster