Gates testified before the House Oversight and Government Reform Committee alongside Joint Chiefs of Staff Chairman Adm. Mike Mullen.
But both Gates and Mullen warned that serious challenges still exist for U.S. forces in Iraq and Afghanistan.
"I believe we have now entered that endgame and our decisions today and in the months ahead will be critical to regional stability and our national security interests for years to come," said Gates. “Even with fewer U.S. troops in Iraq, the positive trends of the last year have thus far held, and in some cases steadily continued in the right direction.
“The continuing drawdown [of troops] is possible because of the success achieved in reducing violence and building Iraq security capacity,” said Gates. "Our casualties have been greatly reduced – even though one is too many – and overall violence is down."
Mullen's and Gates's remarks before Congress came on the eve of the seventh anniversary of the 9/11 attacks and the day after President Bush announced troop reductions in Iraq and the deployment of 4,500 additional troops in Afghanistan.
Mullen also referred to the “the extraordinary success” he thinks U.S. Ambassador to Iraq Ryan Crocker and Gen. David Petraeus have achieved in Iraq, adding that security on the ground has improved and he has witnessed a growing competence of the Iraq military.
But both Gates and Mullen warned that there are great challenges for troops in both Iraq and Afghanistan.
“I'm not convinced we are winning it in Afghanistan," warned Mullen. “I am convinced we can.”
“The U.S. is running out of time to win the war in Afghanistan, and sending in more troops will not guarantee victory,” said Mullen.
“The threat from al Qaeda and other militant groups [in Iraq] has receded, but it is still very real,” said Gates. “In the last few months we have seen a number of suicide attacks, as well as tactical shifts, such as the increased use of women. This is a reminder that al Qaeda still retains its ability to inflict mass casualties.”
Mullen and Gates’ assessment of the surge, which was initially opposed by many lawmakers, including Democratic presidential nominee Sen. Barack Obama (D-Ill.), has been increasingly recognized as a success in recent months.
“The surge has succeeded in ways that nobody anticipated,'' Obama told Fox News’ Bill O’Reilly on Sept. 4. “I’ve already said it’s succeeded beyond our wildest dreams.”