Narrow seas and littoral combat have long been important parts of warfare. The modern age has brought complexity to such aspects of warfare to such an extent that such operations have become very difficult to conduct.

In the early modern era, naval operations were mostly considered amphibious operations or flotilla operations, designed to conduct combat in classic brown and green water. Brown water often included estuaries, riverine, and near coastal areas. The green water zone consisted of the far coastal areas and those out past the closest islands. The 18th and 19th century found these areas tended to differ from blue water or pelagic operations, which are conducted in the open seas.

The modern components or aspects of these littoral operations or narrow seas warfare can be divided into the following categories:

1. Amphibious Operations

2. Flotilla or Small Craft Operations

3. Coastal Defenses and Shore Artillery

4. Aerial Patrols and Air Power

5. Mine Warfare

6. Shallow Aquatic or Submerged Operations

7. Riverine Operations

All of these aspects are part of littoral naval operations, combat in the busiest of maritime zones. As the 21st century has developed, there are many changes as technology advances, especially in the fields of advanced sensors, robotics, digital automations, and new propulsion efficiencies.

 1. Amphibious Operations, as they are currently understood, are very much a product of the 20th century. In more classic times, amphibious operations were even less complex. Most ships, from the ancient Hellenic triremes to the Norse longships, could simply be beached and pulled up onto the shore by the crew. Troops could then just disembark.

During the age of sail, the idea of amphibious operations was to put parties of armed sailors and marines ashore using boats such as long boats and cutters. If a fleet was closer to its port of origin, barges or other shallow draft craft might be used as troop transports to put larger forces ashore. Operations became most complicated when getting cannon and cavalry ashore to build up the army or foreign shore.

As the concepts of steamships and coastal defenses developed in sophistication, it became more complex to get troops ashore if contested or threatened by a nearby army. With the introduction of combined armies became more complex and it took more logistics to transport a truly effective army over the seas as expeditionary forces.

By the 20th century, the need for large numbers of artillery, ammunition, and vehicles increased amphibious supply trains by whole magnitudes. Universal conscription raised armies to vast numbers. This made it easier for nations to have forces on hand in various regions to defend and contest coasts.

The late 19th century’s development of sea mines and long range artillery greatly increased the capacity of coastal forces to defend shores by attacking ships. In earlier eras, cannon could complicate operations, so troops were landed elsewhere for indirect deployment.

Experiences such as the Gallipoli campaign and the Zeebrugge Raid in the Great War discouraged amphibious operations, but the need was still there. Extensive amphibious operations with mixed results also took place in the Baltic between the Germans and Russians.

The Interwar Era was a major time of development for amphibious operations, most especially by the British Royal Navy and the United States Navy. There was work done by other great powers, including the Soviet Union.

There would be many starts and stops, with real world experience contributed by the Second World War. By war’s end complex operational procedures for combined air support, naval fire support, shore assaults, and logistics were developed.

World War II saw the use of amphibious vehicles, landcrafts or boats, and even small beaching ships all used to get forces onto the beach. These experiences were kept active for most major powers, but with few real world major operations except for rarities, such as the Inchon Landing.

The introduction of helicopters for air assault mission capacity changed how the Western powers conducted amphibious operations. The war developed methods were still valid, but air assault gave troops a fourth way to get ashore.

As the Cold War developed, the smaller and simpler amphibious ships were kept in reserve fleets, but most active ships became more complex with larger amphib warships operating in task forces designed for full naval deployment cruises, and patrols.

These needed long duration ships that could keep sufficient expeditionary forces aboard for long periods. This differed from the war experience of loading forces and then going directly to targeted amphibious assaults.

The 21st century pushed amphibious operations beyond the horizon as missilery made any coastal area lethal for ships. This created a need for new doctrine development to successfully conduct amphibious assaults. Air transport could only put light infantry ashore. Amphibious vehicles were hazardous to use for long range transport. Landing craft were more ideal, but were large enough to draw long range fire.

Mine warfare also would prove a detriment to amphibious assault throughout the Cold War from the Korean Conflict up through Desert Storm.

2. Flotilla or Small Craft Operations in littoral zones have been a major aspect of maritime activities since the end of the age of sail. As such writers Corbenett and Coldwell have observed, the small ships of the age of sail were no true threat to ships frigate size and larger, even though smaller ships such as sloops, schooners, and barges had their own roles to play in naval warfare. The introduction of steam power and torpedoes, however, changed the whole equation of the effectiveness of smaller combat craft.

Steam power allowed small crafts to maneuver anywhere that its hull had draft to go. The introduction of anti-ship weapons that could damage the largest warship, but be carried by war boats led to the creation of torpedo boats.

In 1878, HMS Lightning was the first true torpedo boat. The first combat action of a torpedo boat was a Russian torpedo boat against the Ottoman Intibd on 16 January, 1878. The first sinking was against the Chilean Blanco Encalada in 1891.

All of this led to a flurry of activity in the last two decades of the 19th century to see if a small craft could be developed to counter capital ships. Mix with other naval technology trends this also led to the development of destroyers and submarines. But the torpedo boats would be dangerous to warships, but not a true paradigm change to naval warfare.

The drive to develop torpedoes and the introduction of machine guns, light artillery, and light mortars led to a renaissance for small combat craft and the introduction of a wide range of boats, including patrol boats, torpedo boats, and many others.

The 20th century saw missiles added to ocean going boats creating yet another deadly threat against warships. Missiles had ranges out past one hundred kilometers. This would lead to the missile boat or missile cutter in the Six Day War, the Indo-Pakistan 1971 War, the Yom Kippur War, and the Battle of Latakia.

3. Coastal Defenses and Shore Artillery have greatly increased in effect over the past two centuries. The start of the Napoleonic Era saw smoothbore cannon able to threaten ships and boats out to approximately three nautical miles. These were often emplaced in fortresses and artillery batteries. Such cannon were not very mobile and had to be transported and put into position.

Field artillery was more able to be moved around in reaction, but fixed artillery did not have the range of heavier artillery used in siege warfare and long range artillery.

The shift of artillery shells, breech loading, and rifles changed the very nature of artillery. Coastal defenses continued to have the range of capital ships. And just as the age of cannon, the rifle artillery could keep the same balance of tactical power, just with ranges out to dozens of nautical miles.

The introduction of anti-ship and anti-air surface launched missiles allowed nations to exert threatening control over sea surfaces and air space out to dozens if not hundreds of nautical miles.

4. Aerial Patrols and Air Power changed how operations were conducted in littoral zones.

In the Great War, aerial patrols flew reconnaissance for naval forces using airplanes and airships. Attempts to bomb ships from long range aircraft and tactical aircraft had mixed results throughout the Great War. Some damage was successfully done via aerial attacks, but the technology was not sophisticated enough to truly make a tactical difference. Yet, it does show what had become possible.

The interwar saw extensive development of aerial attack options. In the matter of anti-ship and anti-maritime torpedoes, bombs, machine guns, and cannons were all developed. Ships were mostly targeted by bombs and torpedoes. Landbound aircraft, both small craft and multi-engine, could greatly endanger any ship getting close to a hostile shore.

As World War II would bring all of this to the ready; to control a littoral zone required air superiority.

The Cold War saw the introduction of missiles, jet engines, and helicopters. All three technologies brought new capacities to the littoral zone. Jets allowed even faster reactions and attacks for aerial operations. That extended the distance of imminent threat of land based aircraft to reach much further. Helicopters created a new type of aircraft that while slower and shorter range then fixed wing aerodynes, were cheaper to operate and could operate from far more austere sites. This allowed helicopters to be stationed in many places to respond rapidly where fixed wing aircraft take more infrastructure and are tied more to their basing.

5. Mine Warfare has also played an extensive part in the changing nature of littoral maritime operations.

The American Civil War saw extensive use of sea mines by the Confederate Rebels in attempts to secure their harbors. The Union Navy had to overcome those sea mines to press home their blockade strategy.

By the end of the 19th century, mines became a standard part of naval strategy. The sea mines had been developed into a more sophisticated technology. Both contact and captor mine technology had advanced and become far more reliable. Also, mines could be anywhere, free floating, or semi-permanent in place, by the time of the Great War.

The Great War would see defensive and offensive uses of minefields, and hundreds of ships would be damaged by mines. By the war’s end, mines were being laid by ships, boats, aircraft, and submarines.

Throughout this period, minesweeping proved to be very difficult and dangerous. Mine anchor lines had to be cut or snagged. Then mines had to be disarmed or harmlessly exploded.

The Interwar Era and World War II saw advances in triggers for mines with magnetic resonance as well as remote and contact triggers. These periods saw improvements in mines using magnetic and hydrophone triggers.

In the Cold War, programmable triggers made mines very sophisticated. It became possible for sea mines to be laid using new methods such as anchored, drift, and bottom laying. Mines were made new durations and with onboard munitions, torpedoes or missiles, mobile mine, nuclear mine, and other rigging systems. Damage could be direct damage, bubble jet, or shock wave.

Mine sweeping has become an equally complicated and difficult technology process. Processes were developed to be a sweep structure to hit the mines, a cutting device to cut anchor lines, and then a decoy could set off a mine simulating a ship.

Mine hunting is a modern method. The individual mines are detected and identified. Then each mine is specifically targeted for destruction.

6. Shallow Aquatic or Submerged Operations have become major operational domains for the 20th century. The early submarines were more submersibles, but were operationally effective by the Great War.

The 19th century saw attempts to develop submersibles throughout the period, even some in the late 18th century. All of their effects were experimental or desperate.

The 20th century saw smaller submarines developed. Also, the advancement of both robotic submersible and diving gear added a whole new capacity to operate in the underwater environment of the littoral zones.

Civilian and scientific reasons existed to develop capacities in this area as much as the military. Post World War II saw diving systems refined, robotic undersea craft developed, and mini-submarines to be extensively developed.

There are even recreational and criminal uses of submersibles.

7. Riverine Operations have their history as long as humans have been putting boats in water. This means that rivers and their estuaries have always been of vital interest to human political organizations from ancient villages to modern nation states.

Rivers are the main transport methods of many nations. And the mouths of major rivers tend to make good harbors and develop into major cities.

This means that many maritime activities will be close to river estuaries and mouths, and that riverine activity of a military nature can overlap other littoral zone operations. This has a large impact upon the other aspects or components.

All of these components have led to the growing complexity of operations in the littoral zones for maritime activity. The 21st century is seeing all components so far discussed developing capacity as the global technology advances toward the 4th industrial revolution.