U.S. Sen. Ben Nelson says he's closely watching troop buildup and other developments in Afghanistan.
The Nebraska Democrat's remarks came in a column he released this week.
Nelson is chairman of the Senate Armed Services Subcommittee on
Personnel. He says, "America is at a tipping point in Afghanistan," and that success hinges on a functioning Afghan government able to provide protection and basic services for its citizens.
Nelson says he has sent a letter to Admiral Mike Mullen, chairman of the Joint Chiefs of Staff, saying the U.S. needs to establish benchmarks to measure the success of the military effort in Afghanistan.
Nelson says that would help the American people see progress being made and the challenges that remain.