In memoir, Bush defends waterboarding, admits mistakes

(CNN) -- After staying largely mum on the political scene since leaving office almost two years ago, former President George W. Bush will reveal his thoughts on the most historic -- and controversial -- parts of his presidency with the release of his memoir Tuesday.
In the 481-page book, Bush shares his thoughts on the 9/11 attacks, Hurricane Katrina and what he calls the "worst moment" of his presidency.
The 43rd president also takes responsibility for giving the go-ahead for waterboarding terror suspects, which has touched off a new round of criticism of Bush and calls for his prosecution. He says that he decided not to use two more extreme interrogation methods, but did not disclose what those were.
In the book, Bush says the terrorist attacks on the United States on September 11, 2001, gave his administration a clear goal and him the resolve to find out who was responsible and "kick their ass."
"In a single morning, the purpose of my presidency had grown clear: to protect our people and defend our freedom that had come under attack," he writes.
He describes his reaction when his then-National Security Adviser Condoleezza Rice informed him of the crash of a third airplane into the Pentagon.
"I sat back in my seat and absorbed her words. My thoughts clarified: The first plane could have been an accident. The second was definitely an attack. The third was a declaration of war," the former president writes.
"My blood was boiling. We were going to find out who did this, and kick their ass."
In revealing the decision points that led him to choose waterboarding as an interrogation technique, Bush says, "CIA experts drew up a list of interrogation techniques. ... At my direction, Department of Justice and CIA lawyers conducted a careful legal review. The enhanced interrogation program complied with the Constitution and all applicable laws, including those that ban torture.
"There were two that I felt went too far, even if they were legal. I directed the CIA not to use them. Another technique was waterboarding, a process of simulated drowning. No doubt the procedure was tough, but medical experts assured the CIA that it did no lasting harm."
Bush further declares that the new techniques proved effective, yielding information on al Qaeda's structure and operations, and leading to the capture of Ramzi bin al Shibh, the logistical planner of the 9/11 attacks who was captured on the first anniversary of the attacks.
And if there were any lingering doubts or conflict about the use of waterboarding, Bush discloses that he received reassurance from an unlikely source: terror suspect Abu Zubaydah.
The former president writes, "His understanding of Islam was that he had to resist interrogation only up to a certain point. Waterboarding was the technique that allowed him to reach that threshold, fulfill his religious duty, and then cooperate."
Bush elaborates that Zubaydah gave him a direct instruction, "'You must do this for all the brothers.'"
Intelligence gleaned from interrogations of Abu Zubaydah and other suspects led to the capture of Khalid Sheikh Mohammed, Bush writes. During a raid on Mohammed's compound, agents discovered more plans for terrorist attacks on U.S. soil.
Prompted by the discoveries, Director of Central Intelligence George Tenet asked if he had permission to use enhanced interrogation techniques including waterboarding on Mohammed.
Bush exposes his inner thoughts on what led him to reach this decision: "I thought about my meeting with Danny Pearl's widow, who was pregnant with his son when he was murdered. I thought about the 2,971 people stolen from their families by al Qaeda on 9/11. And I thought about my duty to protect my country from another act of terror."
In the book, Bush also recounts the government response to Hurricane Katrina in 2005.
He calls the response "not only flawed" but "unacceptable," and describes his own failures in this way: "As the leader of the federal government, I should have recognized the deficiencies sooner and intervened faster. I prided myself on my ability to make crisp and effective decisions. Yet in the days after Katrina, that didn't happen. The problem was not that I made the wrong decisions. It was that I took too long to decide."
Bush writes he also failed to "adequately communicate my concern for the victims of Katrina" -- a problem he calls one of "perception, not reality."
"Yet many of our citizens, particularly in the African-American community, came away convinced their president didn't care about them."
The former president recently told NBC's Matt Laurer that the "worst moment" of his administration was when rapper Kanye West declared during a Katrina celebrity telethon that "George Bush does not like black people." West has expressed a sympathetic view of Bush's reaction to the comment.
Bush writes the Katrina had a lasting legacy on his second term.
"Just as Katrina was more than a hurricane, its impact was more than physical destruction. It eroded citizens' trust in their government. It exacerbated divisions in our society and politics. And it cast a cloud over my second term."
In the memoir, Bush also compliments Obama's political skills during a meeting before the 2008 election as the financial crisis was coming to a head. He criticizes the performance of his party's nominee, John McCain, in the same meeting.
He also criticizes Senate Majority Leader Harry Reid for the failure of his efforts to reform immigration laws in 2006.
In recent years, Bush has talked about his past problems with alcohol abuse and his 1986 decision to give up drinking completely.
Just days before the 2000 presidential election, news broke that Bush had been arrested for driving under the influence in Maine in 1976.
In his memoir, Bush writes, "Not disclosing the DUI on my terms may have been the single costliest political mistake I ever made."
He says he had decided against doing so because he didn't want to undermine his admonitions to his daughters about drinking and driving.
After the news came out -- so close to election day, Bush writes, he went to bed that night on the campaign trail thinking, "I may have just cost myself the presidency."
CNN's Adam Aigner-Treworgy, John Helton, Ed Hornick, Gabriella Schwarz and Rebecca Sherman contributed to this report.