Globally, terrorists have shown an increasing interest in using small boats to attack military and commercial shipping and maritime facilities. The tactics and techniques of using commercial or non-commercial vessels (under 500 tons) or swimmers to emplace or deliver improvised explosive devices have proven effective and exportable. Contemporary operational practices by transnational terrorist groups include refining proven attack methods, sharing lessons learned, and encouraging others to adopt effective tactics. Thus, the possibility of such attacks in U.S. waters should not be ignored.
The small-boat threat needs to be addressed, but rather than focusing on this particular terrorist tactic, Congress and the Administration should invest in assets that improve the overall security of the maritime domain. The maritime sector is a large and diverse field with unique and daunting threats. Efforts should be expanded to improve U.S. situational awareness and law enforcement response rather than fixating on specific attack scenarios involving small boats or other terrorist threats.
The Small-Boat Threat
The definition of “small-boat threat” encompasses a variety of possible weapon-delivery vehicles, tactics, and payloads. Vessels include everything from large craft such as small freighters, large privately owned yachts, fishing trawlers, and commercial tugs to dinghies, jet-skies, and submarines, including mini-submarines like those used by the Japanese in the attack on Pearl Harbor.
An attack could involve suicide bombers, as in the case of the attack on the USS Cole, or vessels on autopilot or remotely controlled. Improvised explosive devices could be delivered or emplaced by boats or swimmers (assisted or unassisted by breathing devices). This could involve placing a “parasite” on the hull of a craft or deploying tethered (anchored to the sea bottom) or untethered (floating) mines in a sea lane, waterway, or port traffic area.
Besides conventional explosives, the bombers could detonate nuclear, biological, chemical, or radiological devices. Attacks could occur while the targeted ship is docked at shore, approaching a port, sailing in international waters, or in U.S. or Canadian coastal waterways. In addition to ships, attacks could target port facilities; commercial infrastructure (e.g., an entertainment pier, bridge piling, or pipeline); or public events.
How Small-Boat Attacks Are Carried Out
In many respects, small-boat threats resemble other terrorist plots and have a similar signature. They require recruiting, training and planning, surveillance and intelligence collection, operational security, logistical support, rehearsals, information operations, and execution.
On the other hand, these threats have some unique characteristics and considerations. They can require unique attributes and knowledge such as maritime skills (e.g., sailing and scuba diving); familiarity with the target area (such as traffic patterns near a port facility); or explosives training. Unique environmental concerns that can affect the planning and conduct of maritime attacks include weather, tides, and other variables that could affect the dependability and reliability of the strike method. For example, salt, water, and wind can adversely affect weapons delivery and detonation.
Terrorists like predictability. They like to know the obstacles that they will face and the probable results of an attack. Uncertainties in the maritime domain could significantly affect the desirability of employing the small-boat attack method. For example, large public events like a “tall ship” week or a national sporting event might seem inviting targets because of the large crowds of people and the public attention focused on the events. However, large, one-time events are less promising targets because of the additional security and the greater difficulty in predicting the security conditions.
Often, strikes on public venues are more appealing to “lone wolf” attackers who might not weigh the risks and benefits of less well-planned operations as carefully. Likewise, targets such as liquefied natural gas (LNG) tankers or other ships carrying hazardous materials might seem to present tempting opportunities to generate spectacular catastrophic affects. However, from material on the Internet, terrorists already know of the debate over whether or not a small-boat attack could realistically achieve a catastrophic outcome.
On the other hand, normal commercial traffic and port operations bear many of the same characteristics of a desirable terrorist target, including limited responsive security and highly predictable patterns of behavior. For example, high-value ships such as cruise ships and tankers carrying extremely hazardous materials are much more vulnerable when entering or leaving restricted navigable waters along the U.S. coastline, in port areas, or along domestic waterways. During these periods, a large ship typically has a pilot on board, is moving at a low speed, and is following a tight and predictable course because of underwater obstructions and maritime traffic.
Previous al-Qaeda Small-Boat Attacks
The most prominent small-boat attack on a military ship occurred on October 12, 2000, when al-Qaeda operatives detonated a small boat filled with explosives against the hull of the USS Cole, which was refueling in the port of Aden, Yemen. The attack killed 17 U.S. sailors and wounded 39 others. It also garnered much publicity for al-Qaeda, which subsequently highlighted the attack in its recruiting videos and other propaganda.
In October 2002, al-Qaeda undertook its first successful attack against a commercial ship using a small boat. Its operatives rammed the French supertanker Limburg with a small fishing craft packed with explosives. The attack, which occurred while the Limburg was 12 miles off the coast of Yemen, killed one crew member, injured 12 others, and caused a spill of 50,000 barrels of crude oil along 45 miles of coastline.
Other terrorist groups besides al-Qaeda have attempted to use small boats as weapons-delivery vehicles. On November 7, 2000, a Hamas suicide bomber aboard a fishing boat tried to attack an Israeli patrol craft sailing off the Gaza Strip. Alert crew members detected the threat and sank the boat before the Hamas operative could consummate the attack. The Tamil Tigers have also attempted a number of improvised maritime attacks in Sri Lanka.
In addition to terrorist threats, transnational criminals have used similar tactics to smuggle drugs, weapons, humans, and other contraband. These include everything from building mini-submarines to smuggle drugs across the Gulf of Mexico to trafficking Cuban refugees to Key West. Many of the operational practices employed by transnational criminals are adaptable to terrorist attacks. (Conversely, countermeasures designed to address small-boat threats might also be valuable in combating illicit trafficking by small boats.)
How Serious Is the Threat?
The risks associated with small-boat threats are
complex. An assessment of risk combines an
evaluation of criticality (or consequences), threat, and vulnerability. Three major risks connected with small-boat threats should be considered.
The Psychological Impact. Research data make a compelling case that “man-made malicious” events create more fear, apprehension, and uncertainty than natural disasters or accidents. Almost every week, the U.S. experiences maritime incidents that are equivalent to a small-scale terrorist attack in terms of endangering life and property. These range from boating episodes involving individuals to commercial industrial accidents that put hundreds of lives and millions of dollars of infrastructure at risk.
The United States has also experienced a number of large-scale maritime disruptions, which have affected thousands to tens of thousands of lives and hundreds of billions of dollars in damage. These include everything from the Texas City (1947) and San Francisco (1944) disasters, which involved large commercial ships carrying extremely hazardous materials, to Hurricane Katrina, which crippled the ports of New Orleans and Mobile. A terrorist attack of similar scale would certainly have a significantly greater impact on the public, particularly because many Americans have only a minimal appreciation of what occurs in the maritime domain. Anxiety is always greater when individuals are less familiar with the situation.
The impact of a terrorist attack might be reflected in many different behaviors and attitudes, from undermining the confidence of Americans in their government to panic buying because of the fear of economic disruption. The scale and duration of psychological damage could vary significantly, depending on the nature of the incident and the character of the response.
Physical Destruction.A small-boat attack is unlikely to cause a large loss of life or property unless it involves a weapon of mass destruction or highly hazardous material that causes a large-scale fire or explosion. Even a large-scale disaster involving thousands of lives and billions of dollars in damage is unlikely to have long-term negative consequences for the U.S. economy.
In many respects, the response required in the event of a small-boat attack would resemble the response to a fire, explosion, or industrial accident. Thus, many of the current safety measures, equipment, drills, and training required for maritime safety would be applicable to reducing the loss of life and property in the event of a small-boat attack. Likewise, any measures to improve overall safety, firefighting assets, all-hazards disaster response capabilities, search and rescue, other emergency services, and salvage and recovery would contribute to reducing damage in the event of a successful attack.
Disruption of Services.Much of the U.S. maritime infrastructure is clustered near urban centers. Thus, attacks might disrupt mass transit, interrupt delivery of goods and services, or require the evacuation of local populations. Some attacks might seek to disable larger vessels to block waterways, bridges, or tunnels. Physical disruptions would likely be highly localized and have little impact on the overall economy or long-term economic growth, even in the case of large-scale disasters.
Near-term economic impact might be more significant and widespread if terrorists conducted multiple attacks at multiple locations or if the attack affected the national supply chain.