Command of the sea (also called control of the sea or sea control) is a naval military concept regarding the strength of a particular
navy
A navy, naval force, or maritime force is the branch of a nation's armed forces principally designated for naval and amphibious warfare; namely, lake-borne, riverine, littoral, or ocean-borne combat operations and related functions. It in ...
to a specific naval area it controls. A navy has command of the sea when it is so strong that its rivals cannot attack it directly. This dominance may apply to its surrounding waters (i.e., the
littoral
The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal a ...
) or may extend far into the oceans, meaning the country has a
blue-water navy. It is the naval equivalent of
air supremacy
Aerial supremacy (also air superiority) is the degree to which a side in a conflict holds control of air power over opposing forces. There are levels of control of the air in aerial warfare. Control of the air is the aerial equivalent of comm ...
.
With command of the sea, a country (or alliance) can ensure that its own military and merchant ships can move around at will, while its rivals are forced either to stay in port or to try to evade it. It also enables free use of
amphibious operations
Amphibious warfare is a type of offensive military operation that today uses naval ships to project ground and air power onto a hostile or potentially hostile shore at a designated landing beach. Through history the operations were conducte ...
that can expand ground-based strategic options. The British
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against ...
held command of the sea for most of
the period between the 18th to the early 20th centuries, allowing Britain and its allies to trade and to move troops and supplies easily in wartime, while its enemies could not. In the post-
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...
period, the
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...
has had command of the sea.
Few navies can operate as blue-water navies, but "many States are converting
green-water navies to blue-water navies and this will increase military use of foreign
Exclusive Economic Zones
ittoral zone to 200 nautical miles (370 km)with possible repercussions for the EEZ regime."
Historic command of the sea during the age of sail
National capabilities
Historically, many powers attempted to extend command of the sea into peacetime, imposing taxes or other restrictions on shipping using areas of open sea. For example,
Venice
Venice ( ; it, Venezia ; vec, Venesia or ) is a city in northeastern Italy and the capital of the Veneto region. It is built on a group of 118 small islands that are separated by canals and linked by over 400 bridges. The isla ...
claimed the
Adriatic Sea
The Adriatic Sea () is a body of water separating the Italian Peninsula from the Balkan Peninsula. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Sea) to t ...
, and exacted a heavy toll from vessels navigating its
northern waters.
Genoa
Genoa ( ; it, Genova ; lij, Zêna ). is the capital of the Italian region of Liguria and the sixth-largest city in Italy. In 2015, 594,733 people lived within the city's administrative limits. As of the 2011 Italian census, the Province of ...
and
France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...
each claimed portions of the western
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ...
.
Denmark
)
, song = ( en, "King Christian stood by the lofty mast")
, song_type = National and royal anthem
, image_map = EU-Denmark.svg
, map_caption =
, subdivision_type = Sovereign state
, subdivision_name = Kingdom of Denmark
, establish ...
and
Sweden claimed to share the
Baltic Sea
The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain.
The sea stretches from 53°N to 66°N latitude and ...
between them.
Spain
, image_flag = Bandera de España.svg
, image_coat = Escudo de España (mazonado).svg
, national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond")
, national_anthem = (English: "Royal March")
, i ...
claimed dominion over the
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contin ...
and the
Gulf of Mexico
The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...
, and
Portugal
Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...
over the
Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by t ...
and all the
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...
south of
Morocco
Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria t ...
(Hall, 148-9).
Asymmetric countermeasures
During the
age of sail, there were two primary counter measures to another power holding control of the sea:
smuggling, and
privateering
A privateer is a private person or ship that engages in maritime warfare under a commission of war. Since robbery under arms was a common aspect of seaborne trade, until the early 19th century all merchant ships carried arms. A sovereign or deleg ...
. Smuggling helped to ensure that a country could continue trading (and obtaining food and other vital supplies) even when under blockade, while privateering allowed the weaker power to disrupt the stronger power's trade. As these measures, which are examples of
asymmetric warfare
Asymmetric warfare (or asymmetric engagement) is the term given to describe a type of war between belligerents whose relative military power, strategy or tactics differ significantly. This is typically a war between a standing, professional ar ...
, came from non-governmental and sometimes criminal organizations, they fell into disfavor with stronger governments. An annex to the
Treaty of Paris (1856)
The Treaty of Paris of 1856 brought an end to the Crimean War between the Russian Empire and an alliance of the Ottoman Empire, the United Kingdom, the Second French Empire and the Kingdom of Sardinia.
The treaty, signed on 30 March 1856 at ...
banned privateering. That treaty was an oddity in that it was ratified by relatively few countries, but quickly became the ''de facto'' law of the sea.
Historic command of the sea in the era of steam
A more modern countermeasure, similar to privateering, was the use of
submarine warfare by Germany during
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
and
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...
to attack allied merchant shipping primarily in the
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...
,
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ...
, and
Baltic Sea
The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain.
The sea stretches from 53°N to 66°N latitude and ...
.
Historic command of the sea in the era of naval aviation
During
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...
,
aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engine ...
also became an effective countermeasure to command of the sea, since ships could not defend themselves well against air attack. The
Battle of Britain
The Battle of Britain, also known as the Air Battle for England (german: die Luftschlacht um England), was a military campaign of the Second World War, in which the Royal Air Force (RAF) and the Fleet Air Arm (FAA) of the Royal Navy defende ...
was largely an attempt by Germany to eliminate the
Royal Air Force
The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) an ...
, so that it would not be able to defend the
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against ...
from air attack and even to allow a
maritime invasion of Great Britain proper.
Modern command of the sea
![Royal Navy Type 45 destroyer HMS Daring MOD 45154175](https://upload.wikimedia.org/wikipedia/commons/d/de/Royal_Navy_Type_45_destroyer_HMS_Daring_MOD_45154175.jpg)
Advanced navies, with access to
surveillance satellites and large-scale submarine detection systems, can rarely be surprised at sea, but cannot be everywhere. Individual ships of advanced navies can be vulnerable at sea (e.g., the hit by an
Iraqi aircraft-delivered anti-ship missile while patrolling the
Persian Gulf
The Persian Gulf ( fa, خلیج فارس, translit=xalij-e fârs, lit=Gulf of Fars, ), sometimes called the ( ar, اَلْخَلِيْجُ ٱلْعَرَبِيُّ, Al-Khalīj al-ˁArabī), is a mediterranean sea in Western Asia. The bod ...
) or in port (e.g., by the
suicide attack on the .)
"
Blue-water" naval capability
means that a fleet is able to operate on the "
high seas
The terms international waters or transboundary waters apply where any of the following types of bodies of water (or their drainage basins) transcend international boundaries: oceans, large marine ecosystems, enclosed or semi-enclosed region ...
." While traditionally a distinction was made between the coastal
brown-water navy
The term brown-water navy or riverine navy refers in its broadest sense to any naval force capable of military operations in littoral zone waters. The term originated in the United States Navy during the American Civil War, when it referred t ...
, operating in the
littoral zone
The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal a ...
to 200 nautical miles (370 km), and a seagoing blue-water navy, a new term, "
green-water navy," has been created by the U.S. Navy, which refers to the coastal submarines and fast attack boats of many nations, the larger littoral combat corvettes and similar vessels of a substantial number of powers, and amphibious vessels ranging from elderly
LSTs to complex S/VTOL carriers and other specialized ships.
In modern warfare blue-water navy implies self-contained force protection from sub-surface, surface and airborne threats and a sustainable logistic reach, allowing a persistent presence at range. In some maritime environments such a defence is given by natural obstacles, such as the
Arctic
The Arctic ( or ) is a polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), Finland, Iceland, N ...
ice shelf
An ice shelf is a large floating platform of ice that forms where a glacier or ice sheet flows down to a coastline and onto the ocean surface. Ice shelves are only found in Antarctica, Greenland, Northern Canada, and the Russian Arctic. The ...
.
The
US Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...
studied a concept for an economically priced ship capable of surface and subsurface sea control with ASW helicopters and STOVL fighters for light air defense but not large enough to be well suited to power projection known as a
Sea Control Ship
The Sea Control Ship (SCS) was a small aircraft carrier developed and conceptualized by the United States Navy under Chief of Naval Operations Elmo Zumwalt during the 1970s. Currently the term refers to naval vessels that can perform similar d ...
. This small aircraft carrier was not built by the US although a long deck
Amphibious assault ship
An amphibious assault ship is a type of amphibious warfare ship employed to land and support ground forces on enemy territory by an amphibious assault. The design evolved from aircraft carriers converted for use as helicopter carriers (and, a ...
equipped with STOVL fighters and ASW helicopters instead of its primary transport helicopters is operating in a secondary sea control role.
Requirements for modern sea control
During the
Falklands War, the British lacked long-range
Airborne Warning and Control System
Airborne or Airborn may refer to:
Arts, entertainment, and media
Films
* ''Airborne'' (1962 film), a 1962 American film directed by James Landis
* ''Airborne'' (1993 film), a comedy–drama film
* ''Airborne'' (1998 film), an action film sta ...
(AWACS), which led to ship losses and major damage to others, when the
Argentinian
Argentines (mistakenly translated Argentineans in the past; in Spanish ( masculine) or ( feminine)) are people identified with the country of Argentina. This connection may be residential, legal, historical or cultural. For most Argentines, ...
attack aircraft came into the view of ship radar at approximately the same time they would fire antiship missiles, and only a short time before they made bombing attacks. A number of navies have learned this lesson. Many navies with
STOVL
A short take-off and vertical landing aircraft (STOVL aircraft) is a fixed-wing aircraft that is able to take off from a short runway (or take off vertically if it does not have a heavy payload) and land vertically (i.e. with no runway). The ...
carriers have developed helicopter-mounted AWACS like the British and Spanish
Westland Sea King AEW, Italian
EH-101 AEW, and the Russian
Ka-31 AEW helicopter. Recently the French with a new larger CATOBAR
aircraft carrier obtained the US
E-2 Hawkeye AWACS aircraft.
An example for the difference between a blue-water navy and a green-water navy: "...The first should be a 'green-water active defense' that would enable the
People's Liberation Army Navy to protect
China's
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
territorial waters and enforce its sovereignty claims in the
Taiwan Strait
The Taiwan Strait is a -wide strait separating the island of Taiwan and continental Asia. The strait is part of the South China Sea and connects to the East China Sea to the north. The narrowest part is wide.
The Taiwan Strait is itself a ...
and the
South China Sea
The South China Sea is a marginal sea of the Western Pacific Ocean. It is bounded in the north by the shores of South China (hence the name), in the west by the Indochinese Peninsula, in the east by the islands of Taiwan and northwestern Phi ...
. The second phase would be to develop a blue-water navy capable of projecting power into the western Pacific . . . Liu
Central_Military_Commission_1989-97.html" ;"title="Central Military Commission (China)">Central Military Commission 1989-97">Central Military Commission (China)">Central Military Commission 1989-97believed that in order to fulfill a blue-water capability, the PLAN had to obtain aircraft carriers . . ."
Aircraft carriers are deployed with other specialized vessels in
carrier battle group
A carrier battle group (CVBG) is a naval fleet consisting of an aircraft carrier capital ship and its large number of escorts, together defining the group. The ''CV'' in ''CVBG'' is the United States Navy hull classification code for an ai ...
s, providing protection against sub-surface, surface and airborne threats.
As there is no clear definition of a blue-water navy, the status is disputed. Given the importance of naval aviation, the term may be considered to be strongly linked to the maintenance of aircraft carriers capable of operating in the oceans. "In the early 80s there was a bitter and very public battle fought over whether or not to replace
Australia's last aircraft carrier,
HMAS ''Melbourne''. Senior
Royal Australian Navy
The Royal Australian Navy (RAN) is the principal naval force of the Australian Defence Force (ADF). The professional head of the RAN is Chief of Navy (CN) Vice Admiral Mark Hammond AM, RAN. CN is also jointly responsible to the Minister of ...
personnel warned without a carrier, Australia would be vulnerable to all types of threat. One ex-Chief of Navy went so far as to claim that we" (the Australians) "would no longer have a blue-water navy (one capable of operating away from friendly coasts)." Yet although the
Royal Thai Navy
The Royal Thai Navy ( Abrv: RTN, ทร.; th, กองทัพเรือไทย, ) is the naval warfare force of Thailand. Established in 1906, it was modernised by the Admiral Prince Abhakara Kiartiwongse (1880–1923) who is known a ...
operates a sea-going carrier, the RTN is not absolutely a "blue-water navy."
Countermeasures to imposed command
While a ''blue-water navy'' can project sea control power into another nation's littoral, it remains susceptible to threats from less capable forces. Sustainment and logistics at range yield high costs and there may be a saturation advantage over a deployed force through the use of land-based air or
surface-to-surface missile
A surface-to-surface missile (SSM) or ground-to-ground missile (GGM) is a missile designed to be launched from the ground or the sea and strike targets on land or at sea. They may be fired from hand-held or vehicle mounted devices, from fixed ins ...
assets (whether on terrain-following or ballistic trajectories),
diesel-electric submarines, or asymmetric tactics such as Fast Inshore Attack Craft. An example of this vulnerability was the October 2000
USS ''Cole'' bombing in
Aden.
In response to these threats, the U.S. Navy has developed the
Littoral Combat Ship
The littoral combat ship (LCS) is either of two classes of relatively small surface vessels designed for operations near shore by the United States Navy. It was "envisioned to be a networked, agile, stealthy surface combatant capable of defeat ...
(LCS).
See also
* ''
Battleplan
{{italic title
''Battleplan'' is a 2006 military television documentary series examining various military strategies used in modern warfare since World War I. It is shown on the Military Channel in the U.S. and Yesterday. Each episode looks at pa ...
'' (documentary TV series)
*
Air supremacy
Aerial supremacy (also air superiority) is the degree to which a side in a conflict holds control of air power over opposing forces. There are levels of control of the air in aerial warfare. Control of the air is the aerial equivalent of comm ...
*
Naval blockade
A navy, naval force, or maritime force is the branch of a nation's armed forces principally designated for naval and amphibious warfare; namely, lake-borne, riverine, littoral, or ocean-borne combat operations and related functions. It includ ...
*
Sea denial
Sea denial is a military term describing attempts to deny the enemy's ability to use the sea without necessarily attempting to control the sea for its own use. It is a parallel concept to sea control. The two concepts: sea control and sea denial ...
*
Alfred Thayer Mahan
Alfred Thayer Mahan (; September 27, 1840 – December 1, 1914) was a United States naval officer and historian, whom John Keegan called "the most important American strategist of the nineteenth century." His book '' The Influence of Sea Powe ...
*
Maritime republics
The maritime republics ( it, repubbliche marinare), also called merchant republics ( it, repubbliche mercantili), were Thalassocracy, thalassocratic city-states of the Mediterranean Basin during the Middle Ages. Being a significant presence in I ...
*
Maritime power
A maritime power is a nation with a very strong navy, which often is also a great power, or at least a regional power. A maritime power is able to easily control their coast, and exert influence upon both nearby and far countries. A nation that dom ...
*
Thalassocracy
A thalassocracy or thalattocracy sometimes also maritime empire, is a state with primarily maritime realms, an empire at sea, or a seaborne empire. Traditional thalassocracies seldom dominate interiors, even in their home territories. Examples ...
References
Notes
Sources
*
WE Hall, ''Treatise on International Law'', 4th ed., 1895.
{{Authority control
Naval warfare
Military doctrines