Ukraine attacked the Russian Navy sitting at harbor with drones. History says we should have expected such a move: Navalists have always feared harbor attacks. The prospect of ships coming under assault at anchor, while they are mostly helpless, represents a threat not only to the integrity of the fleet, but to the sinews of naval power.
While examples of harbor attacks abound throughout history (including at least one incident in the Peloponnesian War and several in the Napoleonic Wars), a combination of technological and doctrinal innovations conspired to make them more complicated in the 20th century. Indeed, in World War I harbor attacks became quite rare because of a combination of defenses including radio, air reconnaissance, short-range submarines and torpedo boats, and ocean mines. During World War II, however, naval tacticians schemed several innovative ways to attack enemy ships at their most vulnerable.
The first and most notable submarine-led harbor attack took place on Oct. 14, 1939 after U-47 (led by the storied captain Gunther Prien) infiltrated the British naval base at Scapa Flow. Using intelligence collected by aircraft and other submarines, Prien entered the base around midnight through a gap in the British defenses. After identifying a British battleship (the HMS Royal Oak, as it happened), U-47 launched seven torpedoes in three volleys. Four torpedoes struck the battleship, and the Royal Oak sank in about 15 minutes, taking 835 men with her. Prien escaped to a hero’s welcome in Germany, only to die on patrol in March 1941. Over the course of the rest of the war, American and Japanese submarines conducted several harbor attacks (Japanese boats participated at Pearl Harbor), but they didn’t achieve spectacular results. Mines, aircraft, and underwater obstacles made such operations hazardous.
Generally speaking, surprise harbor attacks with gunfire should not have worked in the World War II period; aircraft and patrol vessels should report enemy surface ships at range, allowing time to put in place preparations such as mines, air attacks, and shore artillery. Unfortunately for the French, however, the disarray of the June 22, 1940 surrender to German left their harbor defensive schemes in a shambles. On July 3, 1940, a British force including three battleships, one aircraft carrier, and several smaller vessels appeared near the port of Mers El Kebir and challenged the French fleet therein to surrender or disarm. The French, with four battleships and several modern destroyers, declined, at which point the British opened fire. One French battleship was sunk and two others were damaged, with the loss of some 1,300 men. Operation Catapult was the most successful harbor attack carried out primarily with the gunfire of surface ships during the war, mostly because navies were extremely careful about risking their surface fleet so close to enemy air bases.
Even more than the submarine, the advent of the aircraft carrier rendered surface ships vulnerable even in their anchorages. The first major air attack on an enemy fleet at anchor came on Nov. 11, 1940, when a single British carrier launched twenty-one Swordfish torpedo bombers against the Italian naval base of Taranto. The attack took the Italians by surprise, damaging three Italian battleships – two eventually returned to service – with minimal losses on the British side. The British would raid Italian naval bases several more times during the war, although to minimal effect. The baton was picked up by the Japanese, however, who conducted the massive air raid on Pearl Harbor, along with several smaller raids over the course of 1941 and 1942. Pearl Harbor alone destroyed two battleships and badly damaged several more. Later in the war, the massive carrier flotillas of the Third and Fifth Fleets of the U.S. Navy wreaked destruction at Japanese ports across the Pacific, sinking numerous heavy ships.
Decima Flottiglia MAS (or X Mas), a highly trained unit of Italian maritime commandos, terrorized the Mediterranean from 1940 to 1943. Usually operating at night and using a variety of ingenious delivery systems, the frogmen of X Mas managed to damage or destroy several Royal Navy warships and numerous merchant vessels before the 1943 armistice. Using tiny manned motorboats, they mortally wounded the heavy cruiser HMS York at Souda Bay in 1940. In late 1941, frogmen operating “human torpedoes” (tiny motorized submersibles) attached mines to the hulls of two Royal Navy battleships, putting both out of action for nearly a year.
Back to the Present
Of these methods, the Ukrainian attacks on Sevastopol most resemble this last. It is now no longer necessary for frogmen to risk themselves in such operations, as remotely controlled drones can identify and attack targets directly. Submarines can play a role in such attacks by operating as mother ships to undersea drones. Submarines can also launch cruise missiles and long-range torpedoes into anchorages, while aircraft carriers still retain striking power that they can turn on enemy naval units (although port air defenses are now formidable). In any case, the technologies that navies use to defend ports, and the technologies that they use to attack them, continue to evolve in response to one another. There is little doubt that all major navies will carefully study the Ukrainian attack on Sevastopol, hoping to tease out the offensive and defensive lessons.
Dr. Robert Farley has taught security and diplomacy courses at the Patterson School since 2005. He received his BS from the University of Oregon in 1997, and his Ph. D. from the University of Washington in 2004. Dr. Farley is the author of Grounded: The Case for Abolishing the United States Air Force (University Press of Kentucky, 2014), the Battleship Book (Wildside, 2016), and Patents for Power: Intellectual Property Law and the Diffusion of Military Technology (University of Chicago, 2020). He has contributed extensively to a number of journals and magazines, including the National Interest, the Diplomat: APAC, World Politics Review, and the American Prospect. Dr. Farley is also a founder and senior editor of Lawyers, Guns and Money.