US Defense Secretary Robert Gates flew to Afghanistan today in an unannounced visit to say farewell to US troops and Afghan leaders. Gates, who is retiring at the end of the month, planned to meet with soldiers and Marines in eastern and southern Afghanistan. He also was holding talks with Afghan President Hamid Karzai, who has been sharply critical in recent days of NATO airstrikes that have inadvertently killed and wounded civilians.
Aides said it was Gates' 12th trip to Afghanistan since he became secretary of defense in December 2006. Gates told reporters before arriving in Kabul that although the Afghan war has proved costly—in blood and treasure—budget concerns should not cut short the drive to succeed. "Success of the mission should override everything else because the most costly thing of all would be to fail," he said before flying to Kabul. "Now that does not preclude adjustments in the mission or in the strategy. But ultimately the objective has to be success." (Read more Robert Gates stories.)