In the 1960s MOMA was the center of the contemporary art world. The New Documents exhibit not only cemented photography's acceptance as a fine art form, but influenced a generation of future photographers and photography instructors to emulate the Arbus/Friedlander/Winngrand "school". It also became a template for other institutions and galleries to follow in building collections.

you can agree or disagree with Szarkowski's curatorial abilities and choices, but I think there is little doubt that he was one of the two or three most important people with regards to photography in the last half of the 20th century.