The Brooklyn Bridge says much. It shows architectural tradition in its massive masonry and gothic arches. Unlike England's Houses of Parliament (built roughly in the same Gothic Revival era), the bridge is without filigreed refinement. The unadorned arches look more like functional flying buttresses. Instead of buttressing a cathedral, however, they stand fulcrum to hundreds of steel cables holding modern suspension bridge. They weld together stone and iron, old and new, completing a masterpiece of engineering.
There's much even in the very name The Brooklyn Bridge. Brooklyn: who has not lived there, at least for a time? The bridge made it possible for New York to later annex the borough, enriching the city's wealth of ideas and innovation. These innovations and visions have shaped the nation and the world.
The bridge is a unique icon, sui generis. It reflects the nation better than the classicism of the U.S. Capitol (elegant as it is), or the rote egyptomania of the Washington monument.
The Brooklyn Bridge would be very suitable for use on a new currency, should the U.S. ever be forced to redesign the look of its dollar. (Think of the way the Euro was forced to avoid a face of any one nation, in favor of nameless architectural details.)