Roberts Gates pens tell-all book

"DUTY: Memoirs of a Secretary at War" will be published by Knopf publishing in January 2014. The book cover can be seen here.

Gates served as the Pentagon's top chief during the final years of the Bush administration, replacing Donald Rumsfeld. He stayed in the job after the 2008 election to be Obama's first defense secretary.

During his tenure, he directed the surge in troops in Iraq and then the subsequent drawdown. He also oversaw the brief surge in troops in Afghanistan, was in the White House situation room when Osama bin Laden was killed and prepared the military for the repeal of "Don't ask, don't tell."

The book will be about the conflicts in Iraq and Afghanistan but will also be about "my political war with Congress," Gates writes in his introduction to the memoir.

“This is a book about my more than four and a half years at war,” he writes.
"This book is also about my political war with Congress each day I was in office and the dramatic contrast between my public respect, bipartisanship, and calm, and my private frustration, disgust, and anger. There were also political wars with the White House, often with the White House staff, and occasionally with the presidents themselves."

The memoir will also delve into his relationships with Vice Presidents Dick Cheney and Joe BidenJoe BidenWhy Kaine is the right choice for Clinton Why Mike Pence is the wrong pick on foreign policy Advisers: Trump's revised tax plan will resemble Ryan's MORE, with secretaries of State Condoleezza Rice and Hillary ClintonHillary Rodham ClintonKasich doubts Trump can win Ohio WATCH LIVE: Clinton introduces VP pick Kaine at joint rally Obama calls Kaine an 'optimist,' 'progressive fighter' MORE, and with military leaders including Stanley McChrystal and David Petraeus.

Before he was at the Pentagon, Gates served for more than two decades in the CIA and as CIA director from 1991 until 1993. Obama awarded him the Presidential Medal of Freedom, America’s highest civilian honor.

He became chancellor at the College of William and Mary after he left the Obama administration.