pentagon
US General Accounting Office Building was created in 1951.
Chicago
No
As of 2014, One World Trade Center is the largest and tallest building in the US. It has 104 floors and stands 1,776 feet tall.
white house
White House
The White House.
White House
yesCorrection:No. In Arlington, VA., the Pentagon is the headquarters of the US Department of Defense. It's the world's largest office building as well (Feb 2010).
My state
The Palazzo on the Las Vegas Strip in Paradise, Nevada at 6.9 million square feet has finally passed the Pentagon which held the record since it was completed in 1943.