Two decades ago, Jim Lehrer and Robert MacNeil gave public television a kind of news program that contrasted greatly with the aims of big-network journalism, and the distinction has grown year by year with the decay of the network news divisions. Contributing Editor David Stewart, retired director of international activities at CPB, profiled Lehrer for a forthcoming book on the major programs of public TV. In 1970, on a steaming summer morning in Dallas, I walked into a large room of the public TV station KERA and met Jim Lehrer for the first time. He was seated alone at the end of a long rectangular table, its surface strewn with daily papers, reporters’ notes, overflowing ashtrays and half-empty mugs of coffee. He was studying a clutch of wire service stories, shirt sleeves rolled back, tie pulled away from his unbuttoned collar — the city editor from central casting, I remember thinking.