Got Sea Control?

By Captain Victor G. Addison Jr., U.S. Navy and Commander David Dominy, Royal Navy

Control vs. Command

Our modern understanding of sea control has its origins in the writings of Rear Admiral Alfred Thayer Mahan and Sir Julian Stafford Corbett. Mahan built his theory of "command of the seas" on naval superiority, the concentration of forces, and decisive battles. Corbett subsequently introduced the concept of "control of the seas" as a relative, rather than absolute, condition that applies naval power toward the broader goal of achieving national objectives. According to Corbett, control of the seas is not an end in itself but a means to conduct operations in peace and war that produces effects on land. As our memories of classic blue-water naval battles fade and we find ourselves increasingly engaged in complex littoral operations spanning great distances to counter challenges associated with failing states, regional instability, crime, and violent extremism, the writings of Corbett deserve a closer read.

Recognizing that total control of the seas is not practical, then Vice Admiral Stansfield Turner coined the phrase "sea control" to connote "more realistic control in limited areas and for limited periods of time." 1

British Maritime Doctrine applies these boundary conditions and introduces the notion of purpose.

Sea control is the condition in which one has freedom of action to use the sea for one's own purposes in specified areas and for specified periods of time and, where necessary, to deny or limit its use to the enemy. Sea control includes the airspace above the surface and the water volume and seabed below. 2

Taking this definition one step further by tying sea control directly to specific military objectives provides greater contrast between the littoral and blue-water cases. In blue water, sea-control challenges are likely to come from enemy fleets with naval objectives focused, in the spirit of Mahan, on decisive battle. In the littorals, sea-control challenges are often asymmetric in nature, with military objectives, such as establishing a sea base or conducting an amphibious landing, tied to the broader context of influencing events on shore. A simple definition of sea control that covers the full range of operations, therefore, is the use of the sea as a maneuver space to achieve military objectives.

Beyond Blue Water

The importance of sea control has been understated in recent years because of our longstanding maritime blue-water supremacy. A Cooperative Strategy for 21st Century Seapower categorizes sea control as one of the sea services' six expanded core capabilities, but does not distinguish it. With the continuing proliferation of anti-access and area-denial capabilities around the world, the likelihood is increasing that our local sea control will be challenged, particularly in the littorals. Military planners who require naval power to support operations ashore must take this into account.

As Secretary of Defense Robert Gates remarked in an April 2009 address at the U.S. Naval War College, we face potential conflicts that "will range across a broad spectrum of operations and lethality. Where near-peers will use irregular or asymmetric tactics that target our traditional strengths—such as our ability to project power via carrier strike groups. And where non-state actors may have weapons of mass destruction or sophisticated missiles."

These challenges include unpredictable political circumstances that will restrict overseas access, basing, and overflight rights at inopportune moments. The role of sea control as the most fundamental naval capability that facilitates joint and coalition freedom of action is therefore obvious. Retired Major General David Fastabend, then the U.S. Army's director of Strategy, Plans, and Policy, underscored this critical joint force interdependency during Navy-Army Warfighter Talks in 2008 when he observed, "If you can't provide maritime supremacy, we are buying the wrong kind of Army."

Perhaps the most apt question regarding sea control is not, Can we? but, How do we know if we can? Although joint planners depend on sea power to deliver access, mobility, firepower, and 90 percent of joint-force supplies, there is no generally accepted methodology or doctrine to assess our "sea-control potential" during the campaign-design process. 

Start with a Framework

In keeping with traditional Pentagon staffing principles, a first step in developing such a methodology would be to propose a subjective analytical framework based on sea-control levels, such as the following:

  • Unopposed: Military objectives can be achieved without significant losses.
  • Opposed: Military objectives can be achieved, but losses may be significant.
  • Denied: Military objectives cannot be achieved and/or there is a high probability of unacceptable losses.

    Levels of sea control should be considered in the context of objectives and can be referenced as either an assessment of the operating environment or as a strategy. In this regard, an assessment can be used to define risk and present strategic options to planners in terms of force posture and sequencing. For example, the presence of an adversary's (red) surface action group and shore-based antiship missile batteries may produce a hostile environment for an amphibious landing, but have little impact on allied (blue) submarines and carrier-based aircraft. Allied strategy to successfully execute the amphibious landing could then be to deny the operations area to the red surface action group by using their asymmetric advantage in submarine warfare and to neutralize the missile batteries using their tactical aircraft.

    This simple framework may be adequate for a high-level briefing, but planners require more detailed assessment criteria. While there appears to be an infinite range of elements to assess in determining a navy's sea control potential, the following five provide a starting point

  • Capacity: The combat power a force can bring to bear in a local operations area—a critical factor in attrition warfare.
  • Capability: The attributes a force possesses that determine its potential to disrupt an adversary.
  • Information Dominance: The situational understanding required to operate forces with relative advantage under dynamic circumstances.
  • Tactical Readiness: A force's ability to perform its assigned missions effectively in battle as a function of tactics, training, and procedures.
  • Maneuver Space: The constraints and conditions within which a naval force must operate.

Since these elements are neither discrete nor unique to sea control, it is within the context of the objective that they become relevant. Using the previous example, the allied, or blue, force would have to assess in relative terms, at a minimum, its capacity to wipe out red missile batteries; its capability to disrupt the red surface action group; its tactical readiness to execute the full range of missions culminating in the amphibious landing; its ability to achieve and maintain situational understanding in dynamic conditions; and the impact of the littoral operating environment on red and blue forces. A similar assessment should be conducted from the perspective of the red force.

These elements become increasingly intertwined and difficult to assess when it comes to littoral sea control. A proliferation of disruptive shore-based capabilities can pressure naval forces as they move out of blue water and toward the coast. The at-sea tactical picture becomes more cluttered, making it more difficult to distinguish threats among ambiguous targets. Most important, littoral regions are typically defined by limitations—physical, political, or otherwise—that restrict a naval force's freedom of action. Potentially limitless tactical permutations await the joint sea-control planner.

One method of calibrating a predictive model is to run it against known historical data. By virtue of its overwhelming conventional superiority, the U.S. Navy has operated in a relatively unopposed sea-control environment for many decades and offers limited historical data for developing such a model. Two of America's closest allies, the United Kingdom and Israel, however, have been involved in stressing sea-control cases that are more suitable for analysis.

1982: Britain and Argentina in the Falklands

The 1982 Falklands War is a good example of the challenges navies confront when conducting sea control in the littorals of adversaries at a distance of more than than 8,000 miles. Of the many detailed accounts of the Falklands War, only the memoir of Rear Admiral Sandy Woodward, One Hundred Days, provides the perspective of the task force commander. Woodward notes that "there were several competent organizations which initially suspected the whole operation was doomed." One of these organizations was "the United States Navy, which considered the recapture of the Falkland Islands to be a military impossibility." Although this assessment turned out to be slightly pessimistic, Woodward himself observed that "we fought our way along a knife edge, I realize perhaps more than most that one major mishap, a mine, explosion, a fire, whatever, in either of our two aircraft carriers, would certainly have proven fatal to the whole operation."

A more specific risk estimate from a sea-control assessment would probably not have dissuaded former Prime Minister Margaret Thatcher from ordering the recapture of the Falklands, but it might have influenced campaign strategy. It is illustrative to examine the Falklands campaign as two distinct sea-control problems: blue water and littoral. An actual assessment of these phases by a headquarters staff would require subcategories, weighting factors, and a great deal of PowerPoint. What follows is the distilled version of a relative sea-control assessment that would have been provided for senior Royal Navy leadership.

Blue-Water Phase

In the blue-water phase, the British Task Force's objective was to rapidly conduct an unopposed transit to the South Atlantic and establish a 200-nautical-mile radius "tactical exclusion zone" around the Falkland Islands in preparation for an amphibious assault. Argentina's objective was to deny the Royal Navy the use of the sea as maneuver space through disruption and attrition, thereby preventing an amphibious assault.

The Scorecard

Capacity: Each side owned sufficient naval assets to defeat the other, but Argentina had a five-to-one advantage in tactical aircraft that could potentially overwhelm the British Task Force's air-defense capacity. The lack of an overmatch by the United Kingdom in this category, which includes the challenge of an 8,000 nautical mile logistics chain, probably influenced the U.S. Navy's dire assessment of the Royal Navy's chances. Advantage: Argentina.

Capability: Argentina's fighter aircraft had superior speed and maneuverability compared with the United Kingdom's Harriers, but the United States leveled the playing field somewhat by supplying the British with the advanced AIM-9 Sidewinder missile for air-to-air combat. The Argentine Navy had a significant advantage with the French Exocet antiship missile, but their supply was limited. In the Royal Navy's favor, its three nuclear fast-attack submarines provided an asymmetric antiship and intelligence-gathering capability for Woodward's task force. Advantage: Toss-up.

Information Dominance: The Royal Navy received strategic intelligence from the United States and derived a great deal of tactical intelligence from their fast-attack submarines. Advantage: United Kingdom.

Tactical Readiness: The British developed dog-fighting tactics that would greatly increase the kill ratio of the Harriers. Additionally, the Royal Navy placed significant tactical emphasis on protecting its aircraft carriers and using forward-operating fast-attack submarines to threaten the Argentine Navy's "high value units." Advantage: United Kingdom.

Maneuver Space: The Royal Navy planned to exploit the vast sea area around the Falkland Islands to position its fleet for tactical advantage, keeping the carriers out of strike range and forcing the Argentine strike aircraft to fly through defensive missile screens. Advantage: United Kingdom.

Overall assessment of sea-control level for the blue-water phase: Opposed.

The military objective of controlling the seas around the Falklands in advance of the littoral campaign phase would be achievable with acceptable losses.

Littoral Phase

The United Kingdom's objective during the littoral sea-control phase was to conduct an amphibious assault that established an onshore launching pad from which to defeat Argentine forces on the Falkland Islands. The choice of amphibious objective area was based primarily on the desire to conduct an unopposed landing operation using naval escorts in the Falkland Sound to blunt the anticipated Argentine air assault. Argentina's objective was to use air power to deny the British task force the necessary maneuver space to conduct the amphibious assault and disable it.

The Scorecard

Capacity: The same blue-water imbalance of power carried forth to the littorals. Advantage: Argentina.

Capability: Once the British task force moved toward its amphibious objective area, it was squarely within range of Argentina's shore-based tactical aircraft and missile batteries, a potentially decisive asymmetric advantage for Argentina. Advantage: Argentina.

Information Dominance: The Royal Navy's forces would be easier to find and fix within the confines of the littoral battlespace, thereby negating their strategic and tactical intelligence advantage. Advantage: Toss-up.

Tactical Readiness: The British advantage in blue-water tactics and training would not necessarily apply in the littorals, where the highly proficient Argentine Air Force would become a greater factor. Advantage: Toss-up.

Maneuver Space: The British Task Force was severely restricted in its ability to maneuver in the littorals and, specifically, in Falkland Sound. Advantage: Argentina.

Overall assessment of sea-control level for the littoral phase: Denied.

The military objective of controlling the Falkland Sound for the amphibious landing would place the task force well within range of Argentina's air force, so the probability of unacceptable losses was extremely high. 

Actual Campaign Summary

During the blue-water phase, the Royal Navy exploited the extensive maneuver space to protect its aircraft carriers from Argentina's 200 jets. Concurrently, Britain's asymmetric undersea warfare advantage became decisive when its fast-attack submarine HMS Conqueror torpedoed Argentina's heavy cruiser General Belgrano. This strategic knock-out punch sidelined the Argentine navy—including its aircraft carrier, the ARA Veinticinco de Mayo—for the rest of the war.

The battle shifted markedly in Argentina's favor during the littoral sea-control phase, because the British task force was constrained by its objective, the amphibious landing, and was forced to operate in the sights of Argentina's modern, shore-based air force. Argentina's potentially decisive asymmetric air-warfare advantage was ultimately squandered by a tactical failure. During the littoral sea-control phase, every single British escort operating in Falkland Sound was hit by bombs dropped from Argentina's air force, but many of the bombs did not explode. Admiral Woodward summarized this aspect of the littoral sea-control phase best when he noted in his memoir, "We lost Sheffield, Coventry, Ardent, Antelope, Atlantic Conveyor, and Sir Galahad," but concluded that if Argentina's bombs had been properly fused for low-level air raids, Britain would have lost the war.

Same Game, New Rules

A new dimension has been added to littoral sea control by what is referred to as "the hybrid threat," which retired Marine Lieutenant Colonel Frank Hoffman defines as any adversary that employs a fusion of "conventional weapons, irregular tactics, terrorism, and criminal behavior in the battle space to obtain their political objectives." For example, the hybrid threat posed by the intersection of Somali pirates and the terrorist organizations al-Shabab and al Qaeda near the Bab-el-Mandeb has provided an unprecedented challenge for Coalition navies struggling to keep one of the world's most strategic oil chokepoints open. Nation states that do not possess the capability to directly challenge powerful navies may also employ hybrid sea-denial strategies. This is particularly relevant if the adversary's objective is not to defeat their enemy in conventional terms, but to undermine political will through a protracted struggle that imposes significant costs.

The 2006 Lebanon War between Israel and Hezbollah provides an example of a struggle for littoral sea control within the context of a hybrid threat. The Israeli Navy possessed a clear overmatch in conventional capabilities and developed its tactics accordingly. There is another perspective—Hezbollah's—that will be considered for this sea-control assessment.

2006: Israel and Hezbollah in Lebanon

During the 2006 Lebanon War, the Israeli Navy's objective was to impose a naval blockade to isolate Hezbollah and thus help to advance Israeli defense force operations ashore. Hezbollah's objective was less complicated: inflict damage on a regional superpower, survive the conflict, and win the public relations war. Since Hezbollah doesn't have a navy, this example typifies the "hybrid sea denial" approach that navies may encounter in the littorals.

The Scorecard

Capacity: The Israeli Navy held an absolute capacity overmatch in regular naval forces, but Hezbollah's hybrid forces were not negligible and had to be considered. Advantage: Israel.

Capability: The Israeli Navy clearly overmatched Hezbollah in conventional capabilities. Hezbollah employed hybrid tactics that included missiles, suicide bombers, crime, manipulation of civilian infrastructure, and propaganda. Advantage: Israel.

Information Dominance: The Israeli Navy possessed significant intelligence, command-and-control, and cyber capabilities, but was not aware of Hezbollah's C-802 antiship missiles that could be fired from trucks against naval targets. Since the Israeli Navy had to operate near shore to maintain a blockade, this simplified Hezbollah's targeting problem. Hezbollah also had significant intelligence resources augmented by capabilities from regional allies and was exceptionally media savvy. Advantage: Toss-up.

Tactical Readiness: The Israeli Navy was tactically proficient and well-defended against the C-802 missile when its use was anticipated. Both the Israeli Navy and Hezbollah are very good at what they do. Advantage: Toss-up.

Maneuver Space: The Israeli Navy was constrained by the littoral operating environment, rules of engagement, military doctrine, and international law. Hezbollah's maneuver space was not similarly constrained. Advantage: Hezbollah.

Overall assessment of sea-control level for the 2006 Lebanon War: Opposed.

The Israeli Navy undoubtedly considered its blockade to be an unopposed sea-control operation based on the complete absence of conventional Hezbollah naval capability.

Actual Campaign Summary

The Israeli Navy ship Hanit was severely damaged by a C-802 missile on 14 July 2006. Following a United Nations-brokered ceasefire, the war ended when Israel lifted its naval blockade on 8 September 2006. The chief of the Israeli Navy resigned in 2007. During a panel discussion at the 2009 Surface Navy Association conference, a senior Israeli naval officer advised against spending too much time in the littorals because of the complex threat environment, emphasizing the point that if you don't have to be there, "don't go there."

The Littoral Truth

SIr Julian Corbett was right: to support joint force, national, and even international objectives, we must operate in the littorals. For powerful navies, the most difficult aspect of operating in the littorals is acquiring the necessary mindset and realizing that the default sea-control level is "opposed." It doesn't seem just that our multibillion-dollar ships can be damaged or even sunk by cheap mines, missiles, or skiffs laden with explosives. But we must realistically admit the possibility. History has shown us that in the complicated littoral sea-control environment, losses are not only possible, they are inevitable. Littoral sea control, therefore, needs to be assessed, not assumed, as an important component of campaign design. Powerful navies may not particularly like the idea of operating in the littorals, but it's where the jobs are.


1. Vice Admiral Stansfield Turner, U.S. Navy, "Missions of the U.S. Navy," Naval War College Review, 1974, Vol. XXVI, No. 5., p. 7.

2. BR 1806 British Maritime Doctrine, Third Edition, 2004, p. 289.

Captain Addison is assigned to the staff of the Deputy Chief of Naval Operations for Operations, Plans and Strategy (N3/N5) as branch head for advanced concepts (N511). He is an oceanographer and former submarine strategic weapons officer.

Commander Dominy is assigned to the Pentagon as the first Royal Navy Liaison Officer to OPNAV N3/N5. A surface warfare officer, he commanded the destroyer HMS Manchester, which was integrated into the USS Harry S. Truman Carrier Strike Group during operations in the Arabian Gulf.




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