Has the United States ever had a weirder president than Richard Nixon? The fact that his only close competitors in this regard are his predecessor, Lyndon Johnson, and his indirect successor, Jimmy Carter, could help to explain why the ’60s and ’70s were such troubled times for this country. But even LBJ (who loved to lecture aides while sitting on the toilet) and Mr. Carter (who claimed to have been attacked by a “killer rabbit” and to have experienced “lust in his heart”) could not match Nixon for sheer bizarreness. Evan Thomas’s terrifically engaging biography contains many choice examples.

In 1968, Nixon “invited Walter Cronkite, the CBS anchorman, up to his room and offered him a drink while declining one himself. Realizing that refusing a drink seemed a little prissy, he said to Cronkite, ‘I tell you what, I’ll have a sherry.’ But that didn’t sound like one of the boys either, so he blurted, ‘In fact, I’ll have a double sherry.’ ”

 “At formal White House dinners, Nixon would position himself to talk to ‘as few people as possible,’ with instructions that no conversation was to last more than five minutes. This was to be rigidly enforced; conversations were to be broken off in mid-sentence if necessary.”

“In St. Petersburg, Florida, a policeman was severely injured when his motorcycle flipped over while driving in the presidential motorcade. In his considerate way, Nixon rushed from his limousine to express his sympathies. As was also his way, he didn’t know what to say, blurting to the policeman who lay bleeding on the ground, ‘Do you like your work?’ ”

These are just three lesser-known illustrations of Nixon’s legendary awkwardness. More famous examples include his 1970 Oval Office meeting with the drug-addled Elvis Presley,whom he deputized as a federal agent in the war on illegal drugs; his predawn visit in 1970 to the Lincoln Memorial, valet in tow, where he engaged in a rambling and loopy conversation with a group of dazed hippies; and his jocular comment to David Frost,before an interview in 1976, “Well, did you do any fornicating this weekend?”

The common theme running through all these anecdotes is that Nixon simply did not know how to interact with people. Yet instead of choosing to spend his life in a monastery or at an accounting office, Nixon chose the most public occupation imaginable. He was, as Mr. Thomas notes, “an introvert in an extrovert’s business,” and it was through sheer force of will that he became “a tireless hand-shaker and baby-kisser.” Indeed, so skilled did he become as a politician that he won four national elections, two as vice president, two as president, the last of these (in 1972) by the widest margin then recorded....