The White House is leaping to Vice President Biden's defense after former Pentagon chief Robert Gates pointedly challenged his judgment in a forthcoming memoir.

Gates' book, "Duty: Memoirs of a Secretary at War," has sent a small shock wave through Washington, with its candid critiques of the Obama administration and particularly of those at the top. Gates left little to the imagination in questioning President Obama's leadership style and commitment to the Afghanistan war. But he was unsparing in his assessment of Biden's contribution.

"I think he has been wrong on nearly every major foreign policy and national security issue over the past four decades," Gates wrote, according to The New York Times.

In a written statement responding to the book excerpts, National Security Council spokeswoman Caitlin Hayden said Obama "welcomes differences of view among his national security team."

But she added: "The president disagrees with Secretary Gates' assessment -- from his leadership on the Balkans in the Senate, to his efforts to end the war in Iraq, Joe Biden has been one of the leading statesmen of his time, and has helped advance America's leadership in the world. President Obama relies on his good counsel every day."

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In excerpts published by the Times and Washington Post, and confirmed by Fox News, Gates called Biden a man of "integrity" but also accused him of "poisoning the well" for military leadership.

The tone of Gates' book is a break from Washington decorum, in which former Cabinet members rarely level tough judgments against sitting presidents. On Obama, he claimed the president was only interested in getting troops out of Afghanistan.

Gates wrote that by early 2010 he had concluded the president "doesn't believe in his own strategy, and doesn't consider the war to be his."

The book is scheduled for a Jan. 14 release by the Knopf DoubleDay Publishing Group.

The 70-year-old Gates wrote that Obama appeared to doubt his own strategy in Afghanistan to the point of being "outright convinced it would fail."

Obama deployed 30,000 more troops to stabilize Afghanistan before starting to remove soldiers in mid-2011, after months of tense discussion with Gates and other top advisers.

Gates said he never doubted Obama's support for the troops, "only his support for their mission."

Gates, a carryover from the George W. Bush administration who worked for every president since Richard Nixon, except Bill Clinton, said that underneath his notoriously calm exterior he was frequently "seething" because he felt Obama and his team had neither trust nor confidence in him.

Despite his criticism of Obama, Gates wrote about the commander in chief's primary Afghanistan polices: "I believe Obama was right in each of these decisions."

He admitted to having "a few issues" with George W. Bush and essentially wrote approvingly of then-Secretary of State Hillary Clinton, whom he described as being "smart, idealistic but pragmatic, tough-minded, indefatigable, funny, a very valuable colleague, and a superb representative of the United States all over the world."