The White House has been occupied by some outsize personalities and towering figures, but Lyndon B. Johnson was as big as Texas. Six-foot-four and physically intimidating, he was the kind of man who \"got bigger as he talked to you.\" He had a heart — sometimes — to match: Unlike many white politicians of his era, Johnson was personally infuriated by racism, and signed into law some of the most important civil rights legislation in American history. But he also had colossal flaws: He regularly let his ambition and hunger for power overshadow his ethics, and he almost certainly stole the 1948 election that sent him to the Senate. Everything about him — good and bad — was larger than life. It\'s no surprise, then, that the man can\'t be explained by just one book. Historian Robert A. Caro published the first volume of The Years of Lyndon Johnson 30 years ago — and three books and more than 3,000 pages later, he still hasn\'t finished telling the story of the temperamental Texan and the country he led during its most tumultuous times. History and literature buffs aren\'t complaining, though — with the release of The Passage of Power, the fourth and penultimate volume of the series, Caro has once again shown that he might well be the greatest presidential historian we\'ve ever had. The Passage of Power begins in 1958, with Johnson contemplating a run for the presidency in the 1960 election. His campaign, such as it was, proved to be an unmitigated disaster. Paralyzed by a lifelong fear of failure, LBJ\'s bid was over before it began. He ended up, of course, as John F. Kennedy\'s running mate, despite an intense hatred of the young senator\'s brother Robert (the feeling was very mutual). Johnson became America\'s 36th president after JFK\'s assassination in Dallas, and in the months afterward managed to shepherd through Congress the Civil Rights Act of 1964 — a piece of legislation that had previously been given up for dead. Although the amount of research Caro has done for these books is staggering, it\'s his immense talent as a writer that has made his biography of Johnson one of America\'s most amazing literary achievements. His chapter on the assassination of Kennedy is unbelievably chilling and powerful, but he manages to find the drama in events you might not expect. Johnson\'s effort to pass a tax bill in 1964, for example, may not sound exciting, but Caro\'s chronicle of the struggle is as absorbing as a great political thriller. Even at more than 700 pages, there\'s not a wasted word, not a needless anecdote — The Passage of Power reads more quickly than books a quarter of its size. Perhaps most impressively, Caro comes closer than any other historian could to explaining the famously complex LBJ. He\'s fascinated by, but not in thrall to, his subject. Johnson, he writes, \"was the greatest champion that black Americans and ... all Americans of color had in the White House, the greatest champion they had in all the halls of government.\" But he was also cursed with a monstrous sense of dishonesty, as well as \"a cruelty, a viciousness, a desire to hurt for the sake of hurting.\" In the end, Caro\'s portrayal of the president is as scrupulously fair as it is passionate and deeply felt. Readers will likely have to wait another few years for the final installment of The Years of Lyndon Johnson, which will cover the period between the president\'s 1964 re-election and his death in 1973. Even in its incomplete form, though, the series is a masterpiece, unlike any other work of American history published in the past. It\'s true that there will never be another Lyndon B. Johnson, but there will never be another Robert A. Caro, either. By writing the best presidential biography the country has ever seen, he\'s forever changed the way we think, and read, American history.