Sea lines of communication

Sea lines of communication(abbreviated asSLOC) is a term describing the primarymaritimeroutes betweenports,used fortrade,logisticsandnaval forces.It is generally used in reference tonavaloperations to ensure that SLOCs are open, or in times of war, to close them. The importance of SLOCs in geopolitics was described inNicholas J. Spykman'sAmerica's Strategy in World Politicspublished in 1942.

China's Critical Sea Lines of Communication. In 2004, over 80 percent of Chinesecrude oilimports transited theStraits of Malacca,with less than 2 percent transiting theStraits of Lombok.Click to enlarge. See also: China'sString of Pearls

In theAmerican Revolutionary Warand theNapoleonic Wars,the SLOCs were, for the most part, in the control of theBritish Navy.When the British lost control of them during the Revolution, the result was the fall ofYorktownand its biggest army and, ultimately, the war. In the Napoleonic era, maintaining belligerence throughout, the British embargoed andblockadedany country associated with Napoleon, which created large economic hardships and dislocations that played a part in people of France becoming disenchanted with Napoleon.

InWorld War IandWorld War II,the British and Germans declared mutual blockade and theKriegsmarineattempted to close the SLOCs fromNorth Americato theBritish Isleswith the use ofsubmarines.In each case theAlliessucceeded inkeeping the sea lanes open.The Germans in each case failed to defeat the British navalblockade of Germany.TheUnited States Navy in World War IIsuccessfullyclosedthe SLOCs to Japan, strangling the resource-poor island nation.

Had theCold Warturned hot, Europe would have required resupply and reinforcement from North America. TheSoviet Navycould potentially threaten and contest Atlantic SLOCs to support ground offensives in Europe.

See also

• Choke point
• Line of communication
• String of Pearls (Indian Ocean)

Further reading

• Mahan, Alfred Thayer (1890).The Influence of Sea Power upon History: 1660–1783.
  • The full text ofThe Influence of Sea Power upon Historyat Wikisource
• Phelan, George R. (1954)."Sea Power and Strategies for the Control of the Seas".Naval War College Review.6(10): 15–37.ISSN0028-1484.JSTOR45104663.
• Underwood, G.L. (1981)."Soviet Threat to the Atlantic Sea Lines of Communication: Lessons Learned from the German Capture of Norway in 1940".Naval War College Review.34(3): 43–47.ISSN0028-1484.JSTOR44642156.
• Noer, John Halvard (1996).Southeast Asian Chokepoints: Keeping Sea Lines of Communication Open.National Defense University, Institute for National Strategic Studies.
• Peele, Reynolds B. (April 7, 1997)."Maritime Chokepoints: Key Sea Lines of Communication (SLOCs) and Strategy".Homeland Security Digital Library.Army War College (U.S.).
• Claxton, Karl (February 20, 2014)."China's sea lines of communication—implications for the South Pacific?".The Strategist.
• Kim, Meoung-Sung (2015)."Sea Lines of Communication Security and Piracy".Strategy21(in Korean).36:150–179.doi:10.22803/strategy21.2015.s36.150.ISSN1226-9212.
• The Future of Sea Lane Security Between the Middle East and Southeast Asia(PDF),Energy Studies Institute,Chatham House, June 23–24, 2015{{citation}}:CS1 maint: others (link)
• Andrews-Speed, Philip; Len, Christopher (February 2016),The Future of the US Security Umbrella for Sea Lines of Communication (SLOCs) between the Middle East and Southeast Asia, and the Future Role of China(PDF),Singapore: Energy Studies Institute
• Mubarok, Achmad Romadon; Putra, Agung Tri (2017),Protection of ASEAN Sea Lines of Communication in Maritime Perspective,6th ICADA 2017 — SSIS
• Rimland, Benjamin (July 25, 2017)."Japan's Maritime Strategy and the Dynamics of Denial".Tokyo Review.
• Tarapore, Arzan (February 9, 2021)."India should prioritise a denial strategy in the Indian Ocean".The Interpreter.Lowy Institute.