that the `` surge '' of 30,000 U.S. troops into Iraq was not the primary reason for the decline in violent attacks . `` It was the surge that provided more resources and a security context to support newly developed techniques and operations , '' Hadley wrote . Woodward , associate editor of the Washington Post , wrote that along with the surge and the new covert tactics , two other factors helped reduce the violence . Watch Bob Woodward explain the strategy '' One was the decision of militant cleric Muqtada al-Sadr to order a cease-fire by his Mehdi Army . The other was the `` Anbar Awakening '' movement that saw Sunni tribes aligning with U.S. troops to battle al Qaeda in Iraq . Woodward told Larry King that while there is a debate over how much credit the new secret operations should get for the drop in violence , he concluded it `` accounts for a good portion . '' `` I would somewhat compare it to the Manhattan Project in World War II , '' he said `` It 's a ski slope right down in a matter of months , cutting the violence in half
WASHINGTON -LRB- CNN -RRB- -- The dramatic drop in violence in Iraq is due in large part to a secret program the U.S. military has used to kill terrorists , according to a new book by Pulitzer Prize-winning journalist Bob Woodward . Bob Woodward 's book , `` The War Within : Secret White House History 2006-2008 , '' came out Monday . The program -- which Woodward compares to the World War II era Manhattan Project that developed the atomic bomb -- must remain secret for now or it would `` get people killed , '' Woodward said Monday on CNN 's Larry King Live . `` It is a wonderful example of American ingenuity solving a problem in war , as we often have , '' Woodward said . In `` The War Within : Secret White House History 2006-2008 , '' Woodward disclosed the existence of secret operational capabilities developed by the military to locate , target and kill leaders of al Qaeda in Iraq and other insurgent leaders . National security adviser Stephen Hadley , in a written statement reacting to Woodward 's book , acknowledged the new strategy . Yet he disputed Woodward 's conclusion