Nope, DECCA was not operated by the USN, it was owned and operated exclusively by the Decca Navigation Co., Ltd. (British). They also leased all the receivers until shortly before they discontinued operations. The Bahamian stations were NOT military operations; they were manned by employees of DECCA. The misconception is probably rooted in the proximity of the AUTEC facility, which WAS a USN operation, and located on Andros. If I'm not mistaken, the AUTEC facility was located close to the Andros DECCA station. The charted "DECCA line", parts of which still exist, was a series of steel pilings that served as ATONs between the Andros and Pipe Cay stations.
The Pipe Cay station is a fun visit, watch out for poison wood and snakes, though! (Never saw snakes, but cruisers who stayed on the wall there for several months said they had to watch they didn't come aboard on the lines!) Eeeek!