A photograph is not just the result of an encounter between an event and a photographer; picture-taking is an event in itself, and one with ever more peremptory rights—to interfere with, to invade, or to ignore whatever is going on. Our very sense of situation is now articulated by the camera’s interventions. The omnipresence of cameras persuasively suggests that time consists of interesting events, events worth photographing. This, in turn, makes it easy to feel that any event, once underway, and whatever its moral character, should be allowed to complete itself—so that something else can be brought into the world, the photograph. After the event has ended, the picture will still exist, conferring on the event a kind of immortality (and importance) it would never otherwise have enjoyed.

— Susan Sontag, On Photography, 1977