The Building of the Pentagon

“I like it because nothing like it has ever been done that way before.” – Pres. Franklin D. Roosevelt commenting on the unique design of the planned War Department headquarters

This “Sunday Edition” of our Memorial Day weekend series takes a look at the slice of U.S. history that led to the construction of the Pentagon, the iconic headquarters of the U.S. Department of Defense. At the time of its completion in 1943, the Pentagon was the largest building in the world. Its current ranking is up for debate but it is still clearly the largest office building in the United States with floor area of 6.5 million square feet, of which 3.7 million square feet are used for offices. It’s also remarkable because despite its immense size the building was designed, approved and constructed in just a year and a half.

The idea to build a new headquarters for the War Department (predecessor to the Department of Defense) was in response to growing war anxiety.  By 1941, World War II was well underway.  Germany had taken control of much of Europe and Japan was at war with China.  Germany, Japan and Italy had already signed the Tripartite Treaty forming the “Axis”. In response, the U.S. War Department was growing at a frenetic pace.  By the Summer of 1941 the 24,000 employees of the War Department were housed in the Munitions Building and 22 other locations including apartment buildings, rented garages and even private homes.

The Munitions Building (and its neighboring Main Navy Building) had been built during World War I as temporary structures on the National Mall but on the eve of World War II they were still in use. Ironically, it was President Roosevelt, in his capacity as Assistant Secretary of the Navy during World War I, that was largely responsible for the construction of these buildings. That they still blighted the Nation’s Capital more than 20 years later was an embarrassment for the President. However, his real motivation to find a better home for the War Department came on June 22, 1941 when Nazi Germany launched Operation Barbarossa, marching more than three million soldiers into the Soviet Union. This remains the largest invasion in world history.

Main Navy Building in the foreground and the identical Munitions Building in the background. Both were built as “temporary” structures on the National Mall during World War I.

The driving force behind construction of the Pentagon was Brig. Gen. Brehon B. Somervell. Somervell determined that the War Department needed a new headquarters capable of housing 40,000 people.  He immediately recognized that land for a building of that size could not be found in the District of Columbia so he looked across the Potomac River to Virginia and found what he felt was the perfect location.  Known as “Arlington Farms” the 67-acre tract was a prime site on high ground directly across the river from the Lincoln Memorial.

Somervell dictated that the building must house 40,000 workers, with parking for 10,000 cars, and be no more than 4 stories tall (the completed building is 5 stories above ground). This design would keep the building low-slung so as respect the sight lines imagined in the L’Enfant Plan but, more importantly, it allowed for the building to be constructed using ramps instead of elevators and a minimum of steel, conserving resources in precious demand as the U.S. prepared its massive military build-up.

Somervell’s edicts created significant design challenges for the architects who found that a traditional rectangular or square structure would not fit on the irregularly shaped  Arlington Farms site.  The solution was to design an asymmetrical pentagon that roughly conformed to the site’s dimensions.

Ultimately, the uproar from defenders of the L’Enfant Plan forced the relocation of the Pentagon site to an area near the former Hoover airport then known as “Hell’s Bottom” (the name an indication of its appeal at that time). Though this larger site could accommodate a different layout it was determined that too much time would be lost re-designing the building and, thus, the Pentagon plans were used, molded into a more uniform shape.

The most amazing feature of the Pentagon is not its design but, rather, the speed in which it was built. In a meeting with his staff on the evening of July 17, 1941, Somervell announced his vision of a consolidated War Building and within one week he had drawn plans, presented them to the President and received approval for the construction. Though the spirited debate over the L’Enfant Plan would cause the site to be relocated and the design adapted, groundbreaking still occurred on September 11, 1941 – just 56 days after the project was conceived. Shortly after construction began, on December 7, 1942, the Japanese bombed Pearl Harbor, and construction was accelerated even more so the first 1 million square feet could be occupied by April 1, 1942. The remainder of the massive structure was dedicated on January 15, 1943, just 16 months after its groundbreaking.

The building was one of the first “fast-track” projects ever attempted, and certainly the grandest. At times construction outpaced the design process. Throughout, every effort was made to spare ornamentation and to minimize use of those materials that were being applied to the war effort. The result was a spartan but highly functional structure – one of the world’s greatest construction feats.

There is something about the Pentagon that, throughout its seven decade history, has inspired people to bold achievements. Perhaps it is love of country that has rallied people to work harder, faster and better to build, and re-build, this symbol of American power and independence. On this Memorial Day we honor those who built the Pentagon and all the men and women working within.

Entire books could be written about the Pentagon and, in fact, many have.  Among the best is The Pentagon by Steve Vogel. If you are looking for some summer reading, we highly recommend it.

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