U.S. military official warns of Afghan challenges

The U.S. military's top officer on Thursday said he fully supported the decision to replace the disgraced commander in Afghanistan and cautioned that the months ahead would be very challenging. Admiral Mike Mullen, chairman of the Joint Chiefs of Staff, said the Afghan war strategy would remain unchanged with Central Command chief David Petraeus replacing General Stanley McChrystal in Afghanistan. "I'm very supportive of the president's decision," Mullen said one day after President Barack Obama's changed the top U.S. commander in Afghanistan. Mullen said he expected a tough time ahead but believed Obama's war strategy was on track. "The strategy hasn't changed and the policy hasn't changed and we are very focused on the time between now and July 2011," Mullen said of the timeline set by Obama to begin a gradual withdrawal of U.S. forces, conditions permitting. Mullen said Petraeus was fully supportive of Obama's policies, including the planned draw down. "We don't know the pace and we don't know the place," Mullen, appearing at an event sponsored by The Hill newspaper, said, adding that a lot can change between now and July 2011. Mullen said he expected to see "indicators of how this strategy is working" by year-end, when the White House plans to review its strategy. He said securing the southern Afghan city of Kandahar, the linchpin of Obama's war effort, would be "an extraordinarily complex challenge." He was confident that drawn-out efforts to secure the town of Marjah, in neighboring Helmand province, would work but would take time. "The indicators are moving in the right direction," Mullen said of Marjah. "It gets darkest right before the dawn in these kinds of operations. "That violence will eventually be tamped down." Mullen said he was hopeful a replacement for Petraeus as the head of Central Command would be found "as quickly as possibly," and expressed confidence in Petraeus's deputy at the command to lead during the transition period.