In addition to being a great statesman, a scientist, a farmer, a musician, and the foremost wine connoisseur of his age, Thomas Jefferson was also an important architect, whose work helped create the neo-Palladian style in the United States. In addition to his homes at Monticello and Poplar Forest, Jefferson designed the Virginia State Capitol and the Rotunda at the University of Virginia. Even had he never done anything else, Jefferson's work as an architect would have made him worthy of being remembered.
Public architecture is a reflection of the society that creates it, and Jefferson liked the Palladian style because he felt it represented the Enlightenment values of rationality and natural rights on which the country had been founded. It's interesting to speculate as to what Jefferson would think of the public architecture of our time.
As an example, compare the New York Public Library Main Branch Building, completed in 1911, with the central branch of the Denver Public Library, finished in 1996. The former building is an excellent example of civic architecture, symmetrical and rational, projecting an image of knowledge as strength. The building in Denver, by contrast, is an irrational mash of colors and shapes, looking like it was dropped into place by a passing plane.
Jefferson would consider modern architecture a travesty of aesthetics and a betrayal of Enlightenment values. Postmodernism would be nothing but nonsense to him, and he would be calling on us to recapture the vibrant architectural quality we had when our country was young.
Whenever any level of government creates a new building, whether it be a post office, train station, city hall, or court building, it should be seen as an opportunity to create a piece of architecture that properly reflects the community and its values. America was founded on Enlightenment values of rationality and progress, and its architecture should reflect that fact.