Whatever one’s view of the possible benefits of the war, the costs have been enormous. More than 3,500 Americans have been killed so far, and hundreds of thousands of Iraqis. Millions of Iraqis, among them much of the educated elite, have fled the country. The one clear winner from the invasion and the consequent civil strife has been neighboring Iran, whose fellow Shiites dominate the Iraqi government. Far from suppressing terrorism, the war has aroused widespread anti-Americanism and bred a new generation of terrorists.

Some Bush critics, starting with his first presidential campaign, have put him down as stupid. He is not stupid. He was an effective, if ruthless, candidate. Some who have dealt with him as president — people outside his circle — have found him informed when he was really engaged with a problem. But his attention to many issues has been fitful. “We’ve got a great chance to establish a Palestinian state,” he said in a 2004 press conference, “and I intend to use the next four years to spend the capital of the United States on such a state.” But for much of the next several years the Bush administration was disengaged from the Israeli-Palestinian conflict.

Bush seems to lack the intellectual curiosity that makes for an interesting mind. For all of Draper’s admirable effort to paint a full picture, warts and all, it is a bit of a struggle to read more than 400 pages about George W. Bush.

Draper admires what he calls the “affable compassion” of Bush as a candidate in 2000, before he turned out to be a hard-line conservative on both economics — lower taxes for the rich — and social issues like stem cell research and abortion. His folksy Texas style, even his clumsiness with words, are attractive to many Americans. His occasional locker-room lingo is more natural than Richard Nixon’s awkward efforts. “We’re kicking ass” in Iraq, he told Australia’s deputy prime minister this year.

But there is another, less attractive part of the Bush persona: the mean-minded frat boy. At the 1992 Republican National Convention, Senator John McCain was about to speak for the re-election of Bush 41 when young George came up to him and said, according to Draper, “You’ve gotta hammer Clinton on the draft dodging.” That from a man who had weaved his way out of serving in Vietnam. McCain replied, “Sorry, that’s not my thing.”

On Jan. 31, 2001, soon after taking office, Bush held a cabinet meeting. When he entered the room, one chair was empty: the secretary of state’s. “Lock the door,” Bush said. A few minutes later Colin Powell could be heard trying the doorknob. The room “erupted with laughter.” Then Bush ordered the door unlocked. He “had made his point,” Draper says; Powell was “not the big dog any longer.” That the president of the United States would want to show how important he was by humiliating Colin Powell speaks volumes.

Draper’s thesis is that the immature Bush was transformed by the terrorist attacks of Sept. 11. “All the man’s undersized, self-conscious ways — the smirk, the reedy defensiveness, the exaggerated imperiousness of his executive stroll — had collapsed into this new persona. ... He was a war president now, and perfectly at ease with the role.”