The Pentagon is the headquarters of the United States Department of Defense, located in Arlington, Virginia. As a symbol of the U.S. military, "the Pentagon" is often used metonymically to refer to the Department of Defense rather than the building itself.

Designed by the American architect George Bergstrom (1876 – 1955), and built by Philadelphia, Pennsylvania, general contractor John McShain, the building was dedicated on January 15, 1943, after ground was broken for construction on September 11, 1941. General Brehon Somervell provided the major motive power behind the project; Colonel Leslie Groves and Major Clarence Renshaw were responsible for overseeing the project for the Army.

The Pentagon is the world's largest office building by floor area. The Pentagon houses approximately 23,000 military and civilian employeeS and about 3,000 non-defense support personnel. It has five sides, five floors above ground (plus two basement levels), and five ring corridors per floor with a total of 17.5 miles (28.2 km) of corridors. The Pentagon includes a five-acre (20,000 m²) central plaza, which is shaped like a pentagon and informally known as "ground zero", a nickname originating during the Cold War and based on the presumption that the Soviet Union would target one or more nuclear missiles at this central location.

On September 11, 2001, the hijacked American Airlines Flight 77 crashed into the western side of the Pentagon, killing 125 people who worked on that side of the building.

300px-The Pentagon US Department of Defense building

Southwest view of the Pentagon with the Potomac River and Washington Monument in background.

History Edit

1945 map of the Pentagon road network, including present-day State Route 27 and part of the Shirley Highway.

Construction Edit

Prior to the construction of the Pentagon, the United States Department of War was headquartered in the Munitions Building, which was a temporary structure erected during World War I along Constitution Avenue on the National Mall. The War Department was spread out in additional temporary buildings on National Mall, as well as dozens of other buildings in Washington, D.C., as well as Maryland and Virginia. In the late 1930s, a new War Department Building was constructed at 21st and C Streets in Foggy Bottom, but upon completion, the new building did not solve the department's space problem, and ended up being used by the Department of State.[4] When World War II broke out in Europe, the War Department rapidly expanded with anticipation of being drawn into the conflict. Secretary of War Henry L. Stimson found the situation unacceptable, with the Munitions Building overcrowded and the department spread out.[5][6]

Stimson told President Franklin D. Roosevelt in May 1941 that the War Department needed additional space. On July 17, 1941, a congressional hearing took place, organized by Virginia congressman Clifton Woodrum, regarding proposals for new War Department buildings. Woodrum pressed Brigadier General Eugene Reybold, who was representing the War Department at the hearing, for an "overall solution" to the department's "space problem", rather than building yet more temporary buildings. Reybold agreed to report back to the congressman within five days. The War Department called upon its construction chief, General Brehon Somervell to come up with a plan.[7]

Main Navy Building (foreground) and the Munitions Building were temporary structures built during World War I on the National Mall. The Munitions Building served as the Department of War headquarters for several years before moving into the Pentagon.Government officials agreed that the War Department building should be constructed across the Potomac River, in Arlington, Virginia. Requirements for the new building were that it be no more than four stories tall, and that it use a minimal amount of steel. The requirements meant that instead of rising vertically, the building would be sprawling over a large area. Possible sites for the building included Arlington Farm, adjacent to Arlington National Cemetery, and the obsolete Washington Hoover Airport site.[8] The Pentagon shape of the building was a result of the shape of Arlington Farms, which was the site originally chosen,[9] however President Roosevelt ended up selecting the Hoover Airport site, as he did not want the new building to obstruct the view of Washington, D.C. from Arlington Cemetery.[10] But, the building retained its pentagonal shape because a major redesign at that stage would have been costly and because Roosevelt liked the design. Freed of the constraints of the asymmetric Arlington Farms site, however, it was modified into a regular pentagon.[11]

On July 28, 1941, Congress authorized funding for a new Department of War building in Arlington, which would house the entire department under one roof,[12] and President Roosevelt officially approved of the Hoover Airport site on September 2, 1941.[13] While the project went through the approval process in late July 1941, Somervell selected the contractors, including John McShain, Inc. of Philadelphia, which had built Washington National Airport, the Jefferson Memorial, and the National Naval Medical Center in Bethesda, Maryland, along with Wise Contracting Company, Inc. and Doyle and Russell — both from Virginia.[14] In addition to the Hoover Airport site and other government-owned land, construction of the Pentagon required an additional 287 acres (1.16 km2), which were acquired at a cost of $2.2 million.[15] The Hell's Bottom neighborhood, a slum with numerous pawnshops, factories, approximately 150 homes, and other buildings around Columbia Pike, was also cleared to make way for the Pentagon.[16] Later on, 300 acres (1.2 km2) of land were transferred to Arlington National Cemetery and to Fort Myer, leaving 280 acres (1.1 km2) for the Pentagon.[15]

Northwest exposure of the Pentagon's construction underway, July 1, 1942Contracts totaling $31,100,000 were finalized with McShain and the other contractors on September 11, 1941, and ground was broken for the Pentagon the same day.[17] Among the design requirements, Somervell required the structural design to accommodate floor loads of up to 150 pounds per square feet, which was done in case the building became a records storage facility at some point in the future, after World War II.[13] A minimal amount of steel was used in construction, which was in short supply during World War II. Instead, the Pentagon was built as a reinforced concrete structure, using 680,000 tons of sand, dredged from the Potomac River, and a lagoon was created beneath the Pentagon's river entrance. To minimize steel, concrete ramps were built rather than install elevators.[18][19] Indiana limestone was used for the building's facade.[20]

Architectural and structural design work for the Pentagon proceeded simultaneously with construction, with initial drawings provided in early October 1941, and most of the design work completed by June 1, 1942. At times, the construction work got ahead of the design, with different materials used than what was specified in the plans. Pressure to speed up design and construction intensified after the Attack on Pearl Harbor, on December 7, 1941, with Somervell demanding that one million square feet of space at the Pentagon be available for occupation by April 1, 1942.[21] David J. Witmer replaced Bergstrom as chief architect on April 11, 1942, after Bergstorm resigned due to charges, unrelated to the Pentagon project, of improper conduct while he was president of the American Institute of Architects.[22]

The soil conditions of the Pentagon site, located on the Potomac River floodplain, presented challenges to engineers, as did the varying elevations across the site, which ranged from 10 to 40 feet (12 m) above sea level. Two retaining walls were built to compensate for the elevation variations, and cast-in-place (Franki) piles were used to deal with the soil conditions.[23] Construction of the Pentagon was completed in approximately sixteen months at a total cost of $83 million.

Protests Edit

Military police keep back Vietnam War protesters during their sit-in on October 21, 1967, at the mall entrance to the Pentagon.The Pentagon became a focus for protests against the Vietnam War during the late 1960s. A group of 2,500 women, organized by Women Strike for Peace, demonstrated outside of Secretary of Defense Robert S. McNamara's office at the Pentagon on February 15, 1967.[24] In May 1967, a group of 20 demonstrators held a sit-in outside the Joint Chiefs of Staff's office, which lasted four days before they were arrested.[25] In one of the better known incidents, on October 21, 1967, some 35,000 anti-war protesters organized by the National Mobilization Committee to End the War in Vietnam, gathered for a demonstration at the Defense Department (the "March on the Pentagon"), where they were confronted by some 2,500 armed soldiers. Abbie Hoffman declared the group's intention of levitating the Pentagon 300 feet (90 m) by means of meditation, wobbling it once in mid-air in order to exorcise evil spirits.[26] On May 19, 1972, the American radicals known as the Weather Underground Organization successfully planted and exploded a bomb in a fourth-floor women's restroom in the Pentagon, in retaliation for the Nixon administration's bombing attacks on Hanoi during the final stages of the Vietnam War.

On March 17, 2007, an estimated 4,000 to 15,000 protested the Iraq War. The protesters marched from the Lincoln Memorial, down Washington Boulevard to the Pentagon’s north parking lot. Estimates of actual protesters varies significantly because the march area is in the area of the National Mall, the Lincoln Memorial, and Arlington; and a high number of tourists curiously attracted to the march may have been included in the tallies.

Renovation Edit

Main article: Pentagon Renovation Program Since 1998, the Pentagon has been undergoing a major renovation, known as the Pentagon Renovation Program. This program, scheduled to be completed in 2010, involves the complete gutting and reconstruction of the entire building in phases to bring the building up to modern standards, removing asbestos, improving security and providing greater efficiency for Pentagon tenants. Recently, the process of sealing all of the building's windows began.

As originally built, most Pentagon office space consisted of open bays which spanned an entire ring. These offices used cross-ventilation from operable windows instead of air conditioning for cooling. Gradually, bays were subdivided into private offices with many using window air conditioning units. When renovations are completed, the new space will include a return to open office bays, with a new Universal Space Plan of standardized office furniture and partitions developed by Studios Architecture.

September 11 attacks Edit

Security camera image of Flight 77 hitting the Pentagon.[30]On September 11, 2001, a team of five al-Qaeda affiliated hijackers took control of American Airlines Flight 77, and deliberately crashed it into the Pentagon at 9:37 a.m. EDT as part of the September 11 attacks. All 64 people on the airliner were killed as well as 125 people who were in the building. The impact of the plane severely damaged the structure of the building and caused its partial collapse.[31]

At the time of the attacks the Pentagon was under renovation and several offices were unoccupied, resulting in fewer casualties. Contractors already involved with the renovation were given the added task of rebuilding the sections damaged in the attacks. This additional project was named the "Phoenix Project", and was charged with having the outermost offices of the damaged section occupied by September 11, 2002.[32][33][34]

9/11 anniversary illuminationWhen the damaged section of the Pentagon was rebuilt, a small indoor memorial and chapel were included, located at the point of impact. For the fifth anniversary of the September 11, 2001 attacks, a memorial of 184 beams of light shone up from the center courtyard of the Pentagon, one light for each victim of the attack. In addition, an American flag is hung each year on the side of the Pentagon damaged in the attacks, and the side of the building is illuminated at night with blue lights. After the attacks, plans were developed for an outdoor memorial, with construction underway in 2006. The Pentagon Memorial, which consists of a 2-acre (8,100 m2) park with 184 benches, according to the victims' ages, from 3 to 71, was opened to the public on September 11, 2008.[35][36][37]