Great news for Jeb Bush! Jon Meacham’s new book has just set off several more days of debate about his brother’s decision to invade Iraq.

In Meacham’s forthcoming biography of George H.W. Bush, the old man unloads on Dick Cheney and Donald Rumsfeld for having wrecked his son’s foreign policy. The elder Bush says Cheney joined forces with the “real hard-charging guys who want to fight about everything, use force to get our way in the Middle East.” He accuses Rumsfeld of having an “iron-ass view of everything,” the kind of Bushism that makes no sense linguistically but conveys a mood: Rumsfeld was a foreign-policy militant and a jerk.

The elder Bush isn’t trying to let George W. off the hook. But that’s how many will interpret his comments. Which is a shame, because seeing him as an empty vessel into which Cheney and Rumsfeld poured their imperial militarism is wrong. Cheney and Rumsfeld may have provided the ideology that drove the United States to invade Iraq. But Bush provided the temperament. And that mattered even more.

In Meacham’s book, Bush 41 accuses Rumsfeld of “a lack of humility, a lack of seeing what the other guy thinks. He’s more kick ass and take names.” But those same qualities describe Bush 43.

Observers have long puzzled over the discrepancy between Bush’s behavior after 9/11 and his foreign policy orientation as a candidate in 2000, when he warned that, “If we’re an arrogant nation,” other nations will “resent us,” because “one way for us being viewed as the ‘ugly American’ is for us to go around the world saying, ‘We do it this way; so should you.’”

But the common thread between Bush’s behavior before and after taking office was his penchant for high-risk moves based on his own instincts, irrespective of what anybody else thought. In his terrific book, The Bush Tragedy, Jacob Weisberg notes that in 1977, George W. Bush, who was then drinking heavily, living above a garage and watching his business fail, made the “impetuous” decision to run for a seat in Congress. This “shocked” his parents, who believed political office was something you pursued only after getting rich. Bush lost.

A decade later, when the younger Bush worked on his father’s 1988 presidential campaign, another advisor, Doug Wead, remembers that he “made decisions that just took your breath away, just bam bam bam bam, yes yes yes, no no yes no.”

Later, as managing partner of the Texas Rangers, according to Weisberg, Bush “thought his scouts put too much emphasis on statistics” in their evaluation of players. He, by contrast, “size[d] up people quickly” based on their “character.” It was on this basis that Bush traded Sammy Sosa, who would go on to hit 608 more home runs in his career, to the Chicago White Sox for Harold Baines, who would hit 195. During Bush’s five years running the Rangers, they hugged the bottom of their division. But Bush didn’t change his style. In their book, The Bushes, Peter and Rochelle Schweizer quote a friend on Bush’s own hitting technique: “Wild swings with lots of muscle; but he was swinging so hard, trying so hard, he didn’t take the chance to watch the ball.”

Weisberg and the Schweizers both argue that Bush felt his father had been too cautious in office, which he believed has contributed to the defeat of the old man’s reelection bid. He thought Clinton had been inconsequential too. “Our current president embodied the potential of a generation—so many talents, so much charm, such great skill,” Bush said in 2000. “But in the end, to what end? So much promise to no great purpose.” The “Clinton-Gore administration has coasted through prosperity.”

George W. Bush, by contrast, was determined to be a “game changer.” Even as a candidate, notes former speechwriter Michael Gerson, “[T]he governor consistently pushed his policy team to ‘think big’; his most damning characterization of any proposal was, ‘This is small ball.’”

After 9/11, Cheney, Rumsfeld and Paul Wolfowitz pushed for an attack on Iraq, arguing that the true terrorist threat lay not with Al Qaeda but with terrorism’s alleged state sponsors. But Bush could have overruled them. Secretary of State Colin Powell opposed war with Iraq, and National Security Advisor Condoleezza Rice expressed no strong position. Counter-terrorism czar Richard Clarke considered the idea insane.

The reason Bush sided with Cheney and company, I suspect, is because attacking Iraq rather than stopping with the invasion of Afghanistan was the bigger, bolder move. During post-9/11 discussions, Bush often said he didn’t want to “pound sand,” as he believed Bill Clinton had done in response to previous terrorist attacks or “swat flies.” He repeatedly described the “war on terror” as a struggle on the magnitude of the Cold War and World War II.

Bush never tempered this grandiosity with a serious inquiry into the risks. “I’m not a textbook player. I’m a gut player,” he told his National Security Council two weeks after the attacks. According to Condoleezza Rice, there was little Bush disliked more than being told that a foreign policy issue was “complex.” And he didn’t see invading Iraq as particularly complex, in part, according to Iraqi exiles who met the President in January 2003, because he seemed unaware that Iraq was divided between Sunni and Shia Muslims.

One can see why the elder Bush might focus on the roles of Cheney and Rumsfeld in the Iraq War. But it was his son’s own grandiosity and recklessness that empowered them. And, in a painful irony, that grandiosity and recklessness came, in part, from George W.’s determination not to be a president like his dad.