In late 2002, Saddam Hussein seemed more concerned with writing novels than the prospects of an American invasion of Iraq.

Saddam in this pivotal period thought the U.S. knew he had no weapons of mass destruction, Steve Coll writes in the new book “The Achilles Trap.”

While hostile to weapons inspectors and defiant on the world stage, he thought so highly of the CIA’s abilities that he believed the intelligence agency could see through his bluff. He didn’t even bother to come up with a defense plan for the coalition invasion until December 2002.

The March 2003 toppled Saddam but found no weapons of mass destruction. The decision to invade led to the deaths of more than 3,500 American troops in combat, the Pentagon’s casualty tally said. Other consequences included the deaths of more than 110,000 Iraqi civilians in the violence between the invasion and 2009, an Associated Press report from that time said, with other estimates putting the toll much higher.

The book offers a look into the mind of a dictator that Western leaders failed to understand. Coll researched the book using hundreds of hours of tape recordings from Saddam’s meetings, as the dictator lectured his subordinates. The two-time Pulitzer Prize winner sued the Pentagon for access to the tapes, which had been seized by U.S. forces. The book also draws from more than 100 interviews.

While the book’s aim is to understand Saddam, it doesn’t sanitize his brutality. There is a horrific section on the 1988 Anfal campaign to execute thousands of Kurdish civilians. Other chapters detail Iraq’s use of chemical weapons, and the indefinite detentions and torture imposed by the secret police.

Coll describes Saddam’s introduction to U.S. foreign policy through the lens of his cooperation with the CIA during the 1980s. The CIA under Ronald Reagan came to Baghdad offering maps and other forms of military intelligence to help Iraq in its war against Iran.

Saddam did not trust this information and said that the U.S. must be secretly in league with his enemies, Iran and Israel. And his suspicions would be proven right. The U.S. was indeed sending arms to Iran, with Israeli help, in a scandal that would become known as the Iran-Contra Affair.

Saddam would refer to this incident for years afterward, and how it confirmed his views of the U.S. and the CIA as not to be trusted.

The CIA’s role in Iraq forms much of the American narrative in “The Achilles Trap.” Iraq’s defeat in the first Gulf War exposed Saddam’s covert nuclear-weapons program. Much of the first half of the book is about this effort, told through the story of Jafar Dhia Jafar, the would-be Oppenheimer of Iraq.

The CIA was humiliated as the nuclear program was far more advanced than they anticipated, which fed into their distrust of any of Saddam’s claims regarding weapons of mass destruction.

Coll writes that Iraq’s biological, chemical and nuclear arms programs were indeed destroyed after the Gulf War. But Saddam publicly remained cagey about them. Some of the reasons given are not surprising: he feared his enemies in Iran, Israel and internally would take advantage of him, and his own pride would suffer in any public admission of destroying these weapons.

But the book offers another reason. Saddam seemed to be infected with a cynicism that comes from seeing one’s conspiracy theories turn out to be real. He believed the U.S. was arming Kurdish groups against him and was trying to recruit his generals to overthrow him, and he was right. Saddam thought international weapons inspectors were working with the CIA, and he was right, as the book details.

The dictator would tell people that the CIA knew he didn’t have weapons of mass destruction, and the weapons inspections were all a game, with the real goal being his head. Statements by the U.S. saying sanctions would not go away even if Iraq complied with inspections seemed to confirm this thought.

The idea of the CIA making an analytical mistake on the scale of its error about Iraq’s weapons of mass destruction was not part of Saddam’s worldview, Coll writes.

Saddam attributed to malice what “The Achilles Trap” attributes to incompetence. Coll has said he does not believe in conspiracy theories that the U.S. knew Iraq did not have weapons of mass destruction before invading Iraq. The book’s final chapters describe U.S. marching toward war based on a mistake formed out of confirmation bias and an inability to understand Saddam’s intentions.

By the end of “The Achilles Trap,” readers are confronted with the unsettling reality of a mad despot whose actions might have been more rational than they appeared, juxtaposed against an America whose foreign policy often validated the ideas of its adversaries.

“The Achilles Trap” by Steve Coll is available in hardcover and e-book at most major book retailers.