Hechler, a Princeton political scientist and self-proclaimed ""hero-worshipper,"" eagerly joined the Truman White House staff in 1949 as a researcher and speech-writer, and now enthusiastically describes his old boss and what he, Hechler, was able to do for him. That's not said in disparagement: the portions of the book based on second-hand information are scrappy or stale or both. The good and germane story of how Truman adopted his off-the-cuff speaking style was first told in Jonathan Daniels' 1950 bio (on which Hechler draws too), while such momentous but extraneous events as the MacArthur firing are more authoritatively recounted by Robert Donovan. A borderline case is the tale of how lowly State Dept. aide Benjamin Hardy's technical-assistance proposal became Truman's celebrated Point Four program--which does gain coils-of-government interest in Hechler's expansion. He himself was the designated ""local color"" man for Truman's second-term whistle-stop tours--and that's where the book briefly sparkles. Earlier, Hechler has blown up a first-term boner: at a remote Idaho hamlet, Truman had mistakenly assumed that ""Wilmer Coates"" airport was named after a local war hero (the honoree was local teenager Wilma Coates, who'd been killed hedgehopping with her boy friend); in 1950, Hechler demonstrates, HST toured the Northwest saying exactly the right things at every stop. Or, in the words of an appreciative observer: ""if they had crooked cue sticks in the pool hall. . . the President would say something about it."" 'It was Hechler, too, who fed Truman ""scare words""--citations of hoary Republican warnings against agricultural experiment stations, the Hoover Dam, and such. In the ""friendly informality"" of the Truman White House, something clearly clicked between the history-buff president and the politics-buff professor (later, a nine-term West Virginia congressman). It would have made a better article than it does a book--but White House addicts with patience will find their time repaid.