The modern era of defending American harbors with controlled mines or submarine mines began in the post-Civil War period, and was a major part of US harbor defenses from circa 1900 to 1947.
This WW2-era mine, with its anchor, is on display at Fort Warren in Boston Harbor.
The mine casemate at Fort Strong, Long Island, Boston Harbor, once the control point for mines in the southern channels to the harbor.
A mine casemate had a control panel like this for each 19-mine group under its command. The controls were used to test and to fire the mines.
Mine Planter Service
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The U.S. Army Mine Planter Service (AMPS) was an outgrowth of civilian crewed Army mine planter ships dating back to 1904. It was established on July 22, 1918 by War Department Bulletin 43 and placed the Mine Planter Service under the U.S. Army Coast Artillery Corps. Its purview was to install and maintain the underwater minefields that were part of the principal armament of U.S. coastal fortifications, including those at the approaches to the Panama Canal and the defenses of Manila Bay in the Philippines.
USAMP MP-7 Major General Wallace F. Randolph, Army M 1 Mine Planter Hull No. 480. Records (#742), Special Collections Department, J. Y. Joyner Library, East Carolina University, Greenville, North Carolina, USA.
USAMP Major Samuel Ringgold, built in 1904. (National Archives and Records Administration)