Youngblood's finest hour came the day of the JFK assassination. Riding two cars back with the Vice Presidential detail, he threw himself over LBJ covering the Vice President with his own body when the bullets started flying. That was the tragic time in Dallas when all Secret Service precautions failed and Youngblood tells you that Dallas or Berlin, Rome or Delhi, he was always against motorcades which left the presidents -- he served Truman, Eisenhower, JFK, Johnson and, briefly, Nixon -- so exposed and vulnerable to the surging crowds. During his twenty years guarding presidents and vice presidents, Youngblood evinces pride in his cool professionalism, showing a firm custodial attitude toward the men in the White House -- even when they resented his ministrations. Guarding them wasn't always an easy job, either. Truman's famous early morning strolls, Ike's fondness for the golf links, LBJ's peripatetic wandering around the Texas ranch made them sitting ducks! And sometimes the Chief Executive took mischievous delight in evading his protectors -- even LBJ who called Rufe ""pardner"" or ""son"" in his more mellow moments. Anyway, Rule's book is very upright -- stiff may be a better word -- probably from standing too long at attention. Even when he's telling about all the screwballs and malefactors whom the Secret Service nabbed before they could do their worst. But too much of it is just ""Yes, sir,"" ""No, sir"" catering to the whims of presidents who -- Youngblood seems constantly gratified by it -- can be as testy and stubborn as anyone else.