The Finnish born but Detroit raised architect was naturalized just in time to join the OSS (designing missle diagrams). During the 1950s and 1960s, he developed a kind of soft organic modernism that became the jet age American establishment vision of itself. Steel and glass on the one hand, but with smooth flowing lines that seemed to express the possibility of flight.
The Gateway Arch TWA Terminal at JFK Saarinen's natural but rational airport is the perfect backdrop for a sack suit as Steven Spielberg and Tom Hanks demonstrate in "Catch Me If You Can" Pure delight to our contemporary eyes, but to the orthodox modernists who dominated architecture it was heresy. You see, it is not the function of a building to fly. So, obviously, a form that expresses flight cannot follow function.
Some would argue that not a few of Saarinen's designs were not so functional. No one who has ever set foot in the cursed moving terminals at Dulles would disagree.