This article was originally published on Dec 28, 2011.

Most of us woke up on the morning of Aug. 6, 2011, to learn the devastating news that our nation had lost 17 courageous U.S. Navy SEALs along with five other Naval Special Warfare (NSW) personnel, Air Force Special Operations support personnel, U.S. Army air crew, and an Afghan security element. This happened when their CH-47 helicopter crashed after being hit with a rocket-propelled grenade in Afghanistan’s eastern Wardak province. As a former SEAL Team operator, and with a son currently serving as a SEAL, this kind of news is simply the worst. Sadly, too, there have been equally devastating missions, including June 28, 2005, when 11 other terrific SEALs lost their lives – also in Afghanistan – during a foiled mission and doomed rescue attempt, where another Chinook crashed with all aboard.

Men don’t get assigned to a SEAL Team; they volunteer for this routinely extreme and often arduous duty. From World War II and into the modern-day conflict, very exceptional men have volunteered for some very tough assignments, and many have made the ultimate sacrifice. But who are these men? What is their heritage? And what is it that separates them from all others?

Navy SEALs trace their capability origins back to four formidable legacy units formed during World War II. They were the Amphibious Scouts and Raiders, formed in August 1942 for amphibious reconnaissance and commando operations in Europe and the South Pacific; Naval Combat Demolition Units (NCDUs), assault demolitioneers formed in June 1943 and trained almost exclusively for beach obstacle-clearance operations at Normandy and Southern France; Underwater Demolition Teams (UDTs), combat swimmers formed in December 1944 to conduct hydrographic reconnaissance and demolition of obstacles before amphibious landings throughout the Pacific; and the maritime operators of the Office of Strategic Services (OSS).

There was for many years a prevailing understanding that UDT and SEAL Team origins derived from a school and training program set up at the Amphibious Training Base (ATB) at Fort Pierce, Fla., in June 1943. This story was perpetuated by newspaper articles and books written during the postwar period, and, as a result, it became the common understanding among the SEAL and UDT men for decades thereafter. While the great majority of training was conducted at Fort Pierce, recently discovered documentation now portrays a larger picture.

On May 6, 1943, the “Naval Demolition Project” was directed by the Chief of Naval Operations (CNO) “to meet a present and urgent requirement.” The CNO’s directive outlined a two-phase project. The first phase began with a letter to the Chief of the Bureau of Yards and Docks directing dispatch of eight officers and 30 enlisted men for duty with the Operational Naval Demolition Unit and Naval Combat Demolition Unit No. 1, which was to be formed at the Amphibious Training Base, Solomons, Md. Navy Cmdr. John C. Daniel was selected as officer in charge, and the second phase of the project was very much contingent on the success of the first – so he had a lot riding on his shoulders.

Six officers and 18 enlisted men reported for training at Solomons on May 14, 1943, and all came from the Seabee training camp at Camp Peary, Va. These men were given a four-week course of instruction and sent immediately to participate in Operation Husky, the Allied invasion of Sicily, which occurred that July and August. Daniel submitted a report on May 27 that suggested an organization, outlined a detailed training prospectus, and recommended equipment needed to supply an operational unit. He also recommended that the training program (Phase 2) be moved to ATB Fort Pierce, to take advantage of weather for year-round training.

At this juncture, Lt. Cmdr. Draper Kauffman set up the now-famous Naval Combat Demolition Unit training program at Fort Pierce in June 1943. He was assisted by officers brought with him from the Bomb Disposal School in Washington, D.C. (which he established), and he too acquired most of his volunteers from the Seabee training school at Camp Peary. Kauffman is given credit for instituting the infamous “Hell Week,” a period of intense instruction that remains today in the SEAL Basic Underwater Demolition/SEAL, or BUD/S, training program. One of the most significant aspects of this was that it set the stage for both officers and enlisted men to complete the same qualification training side-by-side, which today remains one of the core strengths of the SEAL Teams, and something not duplicated anywhere else in the military.

Kauffman has sometimes also been given credit for establishing the UDTs of the Pacific during World War II, but this too is not factual. The UDTs were formed in December 1943, while Kauffman was still at Fort Pierce. He did, however, leave his training position in April 1944 to become commanding officer of UDT-5, a post he held until the following August, when he became deputy to Navy Capt. (later Adm.) Byron Hall Hanlon, who, as commander, Underwater Demolition Teams, Amphibious Force Pacific, was given the task of organizing the growing number of UDTs, their small armada of High Speed Transports (APDs), the now basic training program at Fort Pierce, and the advanced training school established at Maui, Territory of Hawaii.

Before the naval demolition project was established, however, there were other units formed that developed legacy capabilities to accomplish what we now know as Naval Special Warfare. Two were formed at ATB Little Creek, Norfolk, Va., in August 1942 almost simultaneously. Each was to perform specific missions in Operation Torch, the Allied invasion of North Africa in November 1942, and yet it is doubtful that either knew about the other or their assigned tasks.

The Amphibious Scouts and Raiders (Joint) were formed to reconnoiter prospective landing beaches and also to lead assault forces to the correct beach under cover of darkness. The unit was led by Army 1st Lt. Lloyd Peddicord as commanding officer and Navy Ensign John Bell as executive officer. Navy chief petty officers and sailors came from the boat pool at ATB Solomons, and Army personnel came from the 3rd and 9th Infantry Divisions. These two groups were gathered at ATB Little Creek in late August, where they trained until embarking for Operation Torch in November. The Scout and Raider school was relocated to ATB Fort Pierce in February 1943, and in July it became an all Navy school reorganized to accomplish a training program code-named “Amphibious Roger.” Roger men were being trained for deployment to the Sino-American Cooperative Organization (SACO) in China, where they became known as “Rice Paddy sailors.” Scout and Raider units and capabilities did not survive the postwar period.

During the same period, a specialized naval demolition team was formed with two naval Reserve officers and 17 enlisted men. All were U.S. Navy trained salvage divers. Their crash course at ATB Little Creek during August and September 1942 included demolitions, commando tactics, cable cutting, and rubber-boat training. Their single mission was to demolish a heavily cabled boom blocking the Wadi Sebou River so that USS Dallas(DD 199) could proceed up the river and train her guns on the Port Lyautey airdrome in preparation for attack by embarked Army Rangers. This was a hair-raising story of determination and success; however, the group was disbanded once it returned from Africa. Because they were Navy divers and because they were given training in demolitions, they have often been referred to as underwater demolition men, but they were not. Of interest, every man in this group was awarded the Navy Cross for his actions in this mission.

NCDU personnel trained at Fort Pierce between June 1943 and April 1944 were largely sent to England for the Normandy invasion; however, eight NCDUs were sent to the Pacific, and six of these remained together for the war’s duration. They were the only NCDUs to do so.

By April 1944, a total of 34 NCDUs had collected in England in preparation for Operation Overlord, the amphibious landings for D-Day in France. For the assault, each six-man NCDU was augmented with three U.S. Navy seamen brought from Scotland to assist in handling demolitions, and the resulting nine-man NCDUs were integrated with Army combat engineers to form 13-man gap assault teams. NCDU men suffered 31 killed and 60 wounded, a casualty rate of 52 percent. D-Day remains the single bloodiest day in the history of Naval Special Warfare, although not one NCDU man was lost to improper handling of explosives. The NCDUs at Omaha Beach were awarded the Presidential Unit Citation, one of only three presented for military actions at Normandy. The men at Utah Beach earned the only Navy Unit Commendation awarded for actions on that awful day.

NCDU men were engaged in combat once more during the invasion of Southern France in August 1944, first code-named Anvil and later Dragoon. Several of the NCDUs from Utah Beach were augmented with new units from Fort Pierce to participate in the last amphibious assault of the war in Europe, which had now become a land march toward Germany. All Fort Pierce trained men would now be sent to the Pacific and organized as Underwater Demolition Teams.

A total of thirty 100-man UDTs were formed in the Pacific during World War II, and only four 50-man teams survived during the postwar period. UDT-1 and UDT-3 were homeported in Coronado, Calif., and organized under Amphibious Forces Pacific, and UDT-2 and UDT-4 were sent to ATB Little Creek, and organized under Amphibious Forces Atlantic. These commands, which became UDT-11, UDT-12, UDT-21, and UDT-22 after Korea, were converted to SEAL Teams in 1983 and still serve at these locations.

Probably the most influential World War II unit that would ultimately impact the capabilities of the UDTs, and subsequently the SEAL Teams, was a joint-service component of the Office of Strategic Services (OSS). Many of its capabilities were later adopted by the postwar UDTs, and many of the same capabilities can still be found in today’s SEAL Teams.

On Jan. 20, 1943, a Maritime Section was established within the Special Operations Branch of OSS, with responsibility for planning covert infiltration operations from the sea. On June 10, 1943, the Special Operations Branch was reorganized as the Maritime Unit (MU), with branch status. Its responsibilities included planning and coordinating the clandestine infiltration of agents, supplying resistance groups, engaging in maritime sabotage, and developing special equipment for operations from the sea. OSS MU pioneered U.S. capabilities in maritime sabotage through use of special-boat infiltration techniques and tactical combat diving using flexible swim fins and facemasks, closed-circuit diving equipment, submersible vehicles, and limpet mines. These capabilities were adopted by the UDTs in 1947, and became hallmarks of SEAL Team capabilities lasting through the modern day.

One individual who stands out as the visionary in bringing the UDTs into the future was Lt. Cmdr. Douglas “Red Dog” Fane, who commanded the Atlantic Fleet UDTs during the postwar period. Fane did everything he could to keep UDT in the spotlight through stunts, demonstrations, experiments, and activities that created numerous newspaper and magazine articles. In 1947, Fane perceptively sought after and enlisted the services of Dr. Christian J. Lambertsen, who, as a U.S. Army medical officer, had been the primary trainer of combat swimmer tactics, techniques, and procedures with OSS MU during World War II. Lambertsen was also inventor of the “Lambertsen Lung,” which was a pure oxygen re-breathing diving apparatus used by OSS during the war and adopted by the UDTs under Fane.

It was Fane and Lambertsen who took the UDTs truly underwater to develop a completely new capability surrounding “Submersible Operations.” This included the first series of submarine lock-out and lock-in operations, and operations with a British-built submersible vehicle called “the Sleeping Beauty.” During 1947 too, Fane had UDT men experimenting with helicopters; however, during this period helicopters did not have the space and lift capacity with which to develop any kind of capability. Moreover, helicopters were also not used tactically during the Korean War period, and didn’t actually become tactical assets until Vietnam.

Fane went on to command the Pacific UDTs during the latter part of the Korean War and authored a book, classically entitled The Naked Warriors, which definitively chronicled the history of NCDU and UDT from World War II through the Korean War period.

The Korean War was a very pivotal period for the UDTs and a prime example of their versatility and adaptability. When hostilities began on June 25, 1950, a 10-man UDT detachment was in Japan with Amphibious Ready Group One. UDT men were performing routine operations involving administrative beach surveys and also assisting U.S. Marine Corps personnel with the training of U.S. Army regimental combat teams in reconnaissance techniques. UDT men were quickly dispatched to Korea, where, on the night of Aug. 5, members of the detachment infiltrated ashore from USS Diachenko (APD 123) aboard inflatable boats to conduct a demolition raid against a train bridge-tunnel near Yosu. This single mission-event in the war became the catalyst that subsequently altered UDT doctrine by providing UDT men with vastly expanded operational capabilities that they employed throughout the war.

By adding to their traditional roles of amphibious reconnaissance and mine and obstacle clearance, the UDT mission, if only temporarily, expanded greatly to include stealthy infiltration from submarines and surface ships to conduct raids and attacks on enemy shipping, port, and harbor facilities; infiltration and intelligence gathering; and covering the withdrawal of friendly forces. UDT men worked closely with CIA personnel, U.S. Marines, Royal Marine Commandos, and South Korean naval commandos in a variety of missions from the sea and ashore.

After the Korean armistice began, the decade of the 1950s was a relatively calm and somewhat “sleepy” period operationally for the UDTs. They honed diving and submarine operational skills, began attending U.S. Army airborne schools, developed maritime parachuting techniques, and experimented extensively with a host of swimmer propulsion and delivery vehicles. Operationally, they made routine deployments with the Amphibious Forces to the Pacific, Atlantic-Caribbean, and Mediterranean areas and conducted numerous training exercises and amphibious landings. World events surrounding places like Cuba, Laos, and Vietnam, however, would soon change all of that.

In the late 1950s, there was a growing and recognized need for military forces with special operations capabilities. This included the Army Special Forces or “Green Berets,” Marine Corps Force Reconnaissance Units, and Navy Underwater Demolition Teams. During his final years in office, President Dwight D. Eisenhower began to proactively engage these specialized forces in small conflicts involving U.S. interests. Foremost were the civil conflicts in Laos and Cuba.

Little has been written about UDT and SEAL Team experiences during the Cuban period, primarily because little has actually been documented, but also because the men involved were sworn to what they thought to be perpetual secrecy and they have taken this commitment quite seriously. Although it is not widely acknowledged, UDT men participated in activities preparatory to the failed Bay of Pigs operation initiated in April 1961. Personnel from UDT-21 and SEAL Teams ONE and TWO were also engaged between 1962 and 1965 in actions and activities surrounding Operation Mongoose, which was a CIA mission designed to overthrow Fidel Castro and his regime. UDT and SEAL Team personnel were also engaged during the Cuban Missile Crisis buildup that occurred during the autumn of 1962.

As early as April 1960, the CIA began to recruit anti-Castro Cuban exiles in the Miami area. At least through July 1960, assessment and training were carried out on the barrier islands of Florida and at various other facilities in South Florida, such as Miami and Homestead Air Force Base. UDT personnel trained 12 hand-selected Cuban exiles in advanced swimming and demolition training at the southern part of Vieques Island, Puerto Rico. These exiles were later moved to an abandoned U.S. Army training base situated on Lake Ponchartrain, La., where the operatives did pool work and trained in rudimentary patrolling, small-boat handling, and maritime infiltration tactics and techniques. They were eventually sent to Puerto Cabezas, Nicaragua, to join the larger invasion force. While the Bay of Pigs invasion was planned under Eisenhower’s administration, the operation was actually executed under the direction of President John F. Kennedy and his national security team.

On the night of April 17, 1961, two landing craft with a CIA “operations officer” and five UDT frogmen entered the Bay of Pigs (Bahía de Cochinos) on the southern coast of Cuba. UDT men also embarked the USS Sea Lion (SS 315) at Mayport, Fla., and evidently were inserted near Havana to conduct harbor and beach reconnaissance. It has never been acknowledged that any U.S. advisors went ashore with their trained operatives.

Operation Mongoose was a somewhat prolonged effort conducted between late 1962 through 1965. It was a highly secret CIA operational plan for the overthrow of the Communist regime in Cuba that aimed to have insurgent operations be performed by Cubans from within Cuba, with outside help from the United States and elsewhere. Personnel from SEAL Team ONE and SEAL Team TWO participated in much of the “unconventional” planning and worked directly with the CIA to establish and operate a series of “safe houses” in and around Miami, Fla. SEAL Team personnel trained Cuban commando teams in small boat operations, beach reconnaissance, and combat swimmer methods. Much of this training was accomplished in austere base situations focused in and around the Florida Keys.

Few conventional thinkers believed that brush-fire wars like Cuba and terrorism would dominate the world scene. Historically, special operations units in most nations have been created to conduct specific missions that conventional forces were either incapable of performing or saw no merit in performing. As a result, and with rare exception, such special units have seldom been recognized for their contributions, and more often than not were disbanded and allowed to fade into obscurity. Moreover, special mission units, by their very nature, conduct covert, clandestine, and other highly sensitive operations, which necessarily place their activities, both past and present, under a cloak of secrecy and generally at odds with conventional thinkers and planners.

It is very likely that the failed Bay of Pigs operation resulted in detailed discussions and decision opportunities between Kennedy and the National Security Council to encourage the military services to accelerate activities involving the capabilities of their special mission units; however, the concept of what would result in the SEAL Teams began as early as 1958, when CNO Adm. Arleigh A. Burke proposed covert military activities to keep the Communist powers off balance.

Burke, who had become the CNO in 1956, championed the cause to devote greater resources to the conduct of limited war. He argued that in an era of nuclear parity, paramount U.S. objectives should be deterrence of general war and the simultaneous maintenance of American global interests. He believed that for the Soviet Union, the fulcrum of struggle would surround the underdeveloped regions of the free world.

In early 1960, Burke directed the Pentagon’s Operational Navy (OPNAV) staff to organize new or existing Navy units for smaller conflicts. He directed the OPNAV staff to study the Navy’s options with respect to unconventional warfare. Among other things the staff suggested “… that the Underwater Demolition Teams and USMC reconnaissance units are organizations capable of expansion into unconventional warfare.” On Sept. 13, an Unconventional Activities Working Group was formally established and reported to the deputy CNO (Plans and Policy). This group was directed to investigate “naval unconventional activity methods, techniques and concepts, which may be employed effectively against Sino-Soviet interests under conditions of cold war.”

The concept for development of an improved “Naval Guerrilla/Counter-guerrilla Warfare” capability within the U.S. Navy and first-time mention of “SEAL” units was delineated in a March 10, 1961, memorandum, wherein Rear Adm. William E. Gentner, Director Strategic Plans Division (OP-06), approved preliminary recommendations of the Unconventional Activities Committee (successor to the Unconventional Activities Working Group). These recommendations were provided to Burke for review, validation, and approval. Included was a recommendation for a wide range of “additional unconventional warfare capabilities within, or as an extension of our amphibious forces.” Operations conducted in “restricted waters” were emphasized – “One unit each is proposed under the Pacific and Atlantic amphibious commanders and will represent a center or focal point through which all elements of this specialized Navy capability (naval guerrilla warfare) would be channeled.” The same memorandum stated that, “An appropriate name for such units could be ‘SEAL’ units, SEAL being a contraction of SEA, AIR, LAND, and thereby, indicating an all-around, universal capability.”

For reasons still unknown, it became widely avowed that President John F. Kennedy personally directed formation of the SEAL Teams, but such is not true. The Navy staff had been working on the problem of unconventional warfare long before Kennedy took office; however, the president tacitly recognized the need on May 25, 1961, in a speech before a special joint session of Congress. This speech became famous because of the president’s affirmation of a national goal to land a man on the moon. In the same speech he also stated that, “I am directing the Secretary of Defense to expand rapidly and substantially, in cooperation with our Allies, the orientation of existing forces for the conduct of non-nuclear war, paramilitary operations and sub-limited or unconventional wars. In addition, our special forces and unconventional warfare units will be increased and reoriented.” That statement is as close as Kennedy ever got to personally directing establishment of SEAL Teams.

After considerable study within the Navy staff, it was determined that expanding the UDT mission would likely hinder their traditional and now doctrinal responsibilities to the Amphibious Force. Thus, it was considered that new units should be established possessing the characteristics of the UDTs, but incorporating new capabilities like those developed and practiced during the Korean War. Because the UDTs were doctrinally tied to Amphibious Force doctrine, they had been consistently denied opportunities to utilize U.S. Army and Marine Corps training schools, or given funding or authorizations to purchase the kinds of equipment needed for expanded naval missions originating from the sea, air, or land. It was intended, therefore, that these new SEAL units would not be doctrinally hindered and would be given freedom to establish a broader and more flexible mission.

Finally, and almost routinely, in a letter dated Dec. 11, 1961, the CNO officially authorized establishment of SEAL Teams in the Atlantic and Pacific Fleets with an effective date of Jan. 1, 1962. SEAL Team ONE was officially established under the command of Navy Lt. David Del Giudice, and SEAL Team TWO under the command of Navy Lt. John Callahan. Organization of these new units represented the culmination of almost four years of investigation into a special naval warfare capability within the Navy.

Several officers on the OPNAV staff signed much of the official documentation that led to establishment of the SEAL Teams. They included Admirals Ulysses S. Grant Sharp Jr., Wallace Beakley, Gentner, and CNO Burke and his successor, Adm. George Anderson. Much of the early work in 1961 was accomplished by Navy Capt. Raymond S. Osterhoudt; however, the vast amount of work can be attributed to Navy Capt. Henry S. Warren, who originated much of the studies, analysis, and correspondence to the fleet commanders. Little did these men know that they were creating a Naval Special Warfare community that would eventually promote many officers to the rank of admiral – including the second and consecutive four-star admiral that currently leads the 60,000 members of the U.S. Special Operations Command.

In November 1963, the SEALs, UDTs, Beach Jumper Units (BJUs), and Boat Support Units (BSUs) were organized as subordinate commands under new staffs called Naval Operations Support Groups (NOSGs). One staff each in the Atlantic and Pacific were established as collaborative planning staffs for the combined units. These NOSGs were the forerunners of the Naval Special Warfare Groups that remain today. BJUs had a classified mission involving fleet cover and deception; however, during this period they were reorganized and tasked for support of smaller conflicts worldwide, especially Vietnam. BJUs were special-mission units originated during World War II, but were eliminated at war’s end. They were established again for Korea, and survived and expanded into the modern day under a series of different names.

The BSUs were a new concept, and the SEALs might not have been as successful as they were in Vietnam without their support. They were made up of fleet personnel specially trained to provide dedicated maritime mobility and boat maintenance. Today’s NSW Special Boat Teams generally trace their origins to BSU-1, which deployed men and boats to Vietnam as Mobile Support Teams (MSTs). These men were tasked with the operation of the Light SEAL Support Craft (LSSC), Medium SEAL Support Craft (MSSC), and Heavy SEAL Support Craft (HSSC).

Although other units supported SEALs during the Vietnam period, only the BSUs and their MSTs were specifically created to support SEALs. The LSSC and MSSC were the first boats designed by the U.S. Navy specifically for SEAL Teams, and specifically for unique riverine infiltration and exfiltration operations. BSUs are often seen as the genesis of today’s Special Warfare Combatant-craft Crewmen (SWCC) community; however, the SWCC heritage also reaches back to World War II with the Scouts and Raiders and their pre-assault missions, and the OSS Maritime Unit, whose mission involved clandestine infiltration and exfiltration of men and supplies in the Balkan Peninsula of Europe and in the Burma area of the Pacific.

SEALs began to establish what would become an exceptional record of accomplishment in Vietnam. The result was that a budding NSW community of specially trained SEAL officers and men continued to strengthen after Vietnam. The Navy established an NSW Naval Officer Billet Code (NOBC) on Jan. 7, 1969, when the Vice CNO Adm. Bernard. A. Clarey approved special warfare as one of the Navy’s four warfare area specialties (surface, subsurface, air, and special warfare) within the unrestricted line 1100 designator system (113X). This was vital to maintaining professionalism, knowledge, and understanding of this special kind of warfare. It is the reason that there are SEAL flag officers today.

At the time of their formation and throughout much of the Vietnam conflict, the existence of the SEAL Teams remained highly classified. It’s difficult to grasp that when the SEAL Teams were formed in January 1962, there was only one team in each fleet, both were commanded by a Navy lieutenant with a complement of 10 officers and 50 men, and that they actually remained that size until a buildup with the rest of the Navy in Vietnam during the mid- to late-’60s. Moreover, both teams struggled to survive drastic downsizing after Vietnam, since there was no doctrinal place for them in the U.S. Navy. While terms like special operations, special warfare, and combat divers are commonplace today, not many years ago they were not used in polite military circles. Moreover, there were only a few in the Navy that fully understood their meaning, and those that did were largely the men in the UDT and SEAL Teams, who reverently referred to themselves as the “Naval Special Warfare community,” which became, and remains, extremely strong and cohesive.

Today there are 10 active-duty SEAL Teams, each made up of more than 200 men and women (SEALs and support and mission-enabling personnel), and each commanded by an 0-6 commander. Two additional SEAL Teams have been organized within the Naval Reserve Component.

SEALs have survived from the earliest days because of the hallmarks of success and operating tenets adopted by them through the actions and activities of their legacy brothers in NCDU, Scouts and Raiders, OSS Maritime, and Underwater Demolition Teams. SEALs are and will remain unique among all special operations forces, because it is they who are called upon when tasks need to be carried out clandestinely; where there is a high security risk; or if the task is a particularly difficult or delicate one, where operations involve working in small numbers under isolated, unsupported, and/or hostile conditions, and where the approach to the target is on or under the water.

This article first appeared in Navy Seals 50: Commemorating the 50th Anniversary of the Establishment of the U.S. Navy SEALs.