问答题 Harry S. Truman liked to say that as president of this country he was its most powerful citizen-but sometimes he added, smiling, the photographers were even more powerful. They could tell the commander in chief where to go, make him move his chair, cross his legs, hold up a letter, order him to smile or to look stern. He acknowledged their power and, as a political matter, deferred to their judgment. What the people thought of their chief executive would to some extent be decided by the photographers and the picture editors. Photographers may claim to be a priesthood interpreting the laws of light, and light is a universal mystery that the picture takers measure with their light meters.