(NEW YORK) -- "Gaps" in President Obama's leadership contributed to the collapse of a "grand bargain" on spending and debt last year, with the president failing to cultivate congressional relationships that may have helped him break through Republican opposition, author Bob Woodward told ABC News' Diane Sawyer.
Woodward's reporting in his new book, The Price of Politics, reveals a president whom he said lacked the "stamina" in turning personal relationships with congressional leaders into action the way some of his predecessors have done.
"President Clinton, President Reagan. And if you look at them, you can criticize them for lots of things. They by and large worked their will," Woodward told Sawyer. "On this, President Obama did not."
"Now, some people are going to say he was fighting a brick wall, the Republicans in the House and the Republicans in Congress. Others will say it's the president's job to figure out how to tear down that brick wall. In this case, he did not."
Asked if Obama simply wasn't ready for the job of being president, Woodward responded:
"I am not ducking this. I am weighing evidence, and there's evidence that he got on top of a lot of things, he did a lot of things. And there's evidence that there are gaps," he said. "He did not fix this."
Woodward places particular blame for the failure to reach a deal with Obama, writing that the seeds of discord were planted early in his administration. He displayed "two sides" of his personality in early meetings with congressional leaders, Woodward said.
"There's this divided-man quality to President Obama always. Initially he meets with the congressional leaders, he says you know, 'We're going to be accommodating, we're going to listen, we're going to talk, we're going to compromise," Woodward said.
"But then they -- Republicans ask some questions and challenge him a little bit and he says, 'Look I won. I'm in charge here,'" Woodward continued. "And the Republicans feel totally isolated and ostracized. And this was the beginning of a war."
Last summer's debate over the debt ceiling was an intense period for the Obama presidency -- and a perilous one for the nation. One White House aide described it as the economic equivalent of the Cuban Missile Crisis; in an interview with Woodward, Obama himself compared the tension during this timeframe with his decision to strike Osama bin Laden's compound.
Tune in to ABC’s World News with Diane Sawyer and Nightline on Monday, Sept. 10, 2012 to see Diane Sawyer's exclusive interview with Bob Woodward.
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