[edzo4]

I thought the water references could relate to the Navy

https://www.nytimes.com/2018/03/04/world/asia/carl-vinson-vietnam.html

March 4, 2018

BANGKOK — For the first time since the end of the Vietnam War, a United States aircraft carrier made a port call in Vietnam on Monday, signaling how China’s rise is bringing together former foes in a significant shift in the region’s geopolitical landscape.

The vessel, the Carl Vinson, anchored off Danang, the central Vietnam port city that served as a major staging post for the American war effort in the country.

[AzNASCARfan]

I am concerned it is warning of a tsunami bomb...
Also thinking rogue sub as in maybe missing Argentinian?

[greeneyes]

very possible - could be both - Q often has more than one meaning.