"Pursuant to this mission, the USS Kidd intercepted a drug-smuggling boat in 1983. When the smugglers refused to yield without force, the problem of passive versus active law enforcement was handled by lowering the Navy ensign on the ship and raising the Coast Guard ensign. The Coast Guard asset USS Kidd then fired on the smugglers’ ship, rendering it immobile and leading to its seizure, along with 900 bales of marijuana."
See The Myth of Posse Comitatus by Major Craig T. Trebilcock, U.S. Army Reserve
Perhaps one US Coast Guard officer could take "command" and make a Navy destroyer a Coast Guard destroyer.
I have a book somewhere called "Florida's Army" published by the Florida National Guard as a fund raiser about 20 years ago. One section is about Florida State Troops, they weren't NG.
Among the State forces were revenue Cutters commissioned in the '20s and earlier to help combat smuggling and to patrol Florida's long coastlines. Any reason it couldn't be done again? Lots and lots of good sized ships in our marinas, some even have helos on board!
Does this mean that the US Army can become National Guard units if need be??
They don't have to. The Navy has had ships assigned to drug interdiction patrols for years now.