It is very rare for an official biography to be also a revisionist biography, but this one is. Usually it’s the official life that the revisionists attempt to dissect and refute, but such is the historical reputation of Henry Kissinger, and the avalanche of books and treatises already written about him, that Niall Ferguson’s official biography is in part an effort to revise the revisionists. Though not without trenchant criticisms, “Kissinger. Volume I. 1923-1968: The Idealist” — which takes its subject up to the age of 45, about to begin his first stint of full-time government service — constitutes the most comprehensive defense of Kissinger’s outlooks and actions since his own three-volume, 3,900-page autobiography, published between 1979 and 1999.