[SteveH]

somehow “cannot be located” seems a bit like military public affairs hyperbole to me...

[Yosemitest]

“cannot be located”

That might mean that the ILLEGAL ALIEN IN CHIEF has pulled out the P-3 Orion Sub Hunters from the Korean/Japanese "theater".
The Yellow Sea is a "shallow" sea, so if the mini-subs “cannot be located”, then they're in the Sea of Japan, or they're in rivers in North Korea, which are also shallow.

[mason-dixon]

“can’t be located”... Have you considered the possibility that these submarines are out of port because of Hurricane Goji tracking over Korean Peninsula? And the smarter “captains” will make emergency “port call” in South Korea to get a good meal for his crew?