The top American commander in Afghanistan faces skeptical lawmakers amid concerns that worsening security conditions demand a greater number of U.S. forces to ensure the gains made in the war-torn country since 2001 aren't lost.

Army Gen. John F. Campbell is slated to testify on Tuesday before the House Armed Services Committee, where members are expected to press him on President Barack Obama's plan to cut American troop levels from 9,800 to 5,500 before he leaves office next January. Obama had backtracked from his initial plan to reduce the U.S. force to 1,000 by the end of 2016.

Republicans have long assailed Obama's exit strategy, arguing that conditions on the ground in Afghanistan, not a calendar, should determine the pace of the withdrawal. With the Taliban staging new offensives and the Islamic State extremist group seeking a presence in Afghanistan, congressional Democrats also are raising the prospect of an extended stay.

"I've always believed that putting a time limit on it is a mistake," Rep. Mac Thornberry, R-Texas, the committee chairman, said Monday. "To say this is going to take five years, 10 years or 50 years, nobody can say that."

Rep. Seth Moulton, D-Mass., warned against a repeat of Iraq. American forces were withdrawn too rapidly and without a long-term political strategy to ensure the progress they made would hold, he said. U.S. troops had to return to Iraq after the resulting instability allowed IS to grow.

"I've never been an advocate for withdrawing troops on a timetable," said Moulton, a former Marine Corps officer who served four tours in Iraq. "If security is worsening with the number of troops we have there now, then we shouldn't cut them below the current level."

Campbell is expected to retire soon and Obama has nominated Army Lt. Gen. John W. "Mick" Nicholson, Jr., to replace him.

Sen. Joe Donnelly, D-Ind., said last week that Congress "desperately" needs an unvarnished assessment of troop requirements even if the recommended number contradicts what Obama has proposed.

"If it's 10,000 that's needed to be effective, then tell us it's 10. If it's (5,000), tell us it's 5," Donnelly said at a Senate Armed Services Committee hearing held to consider Nicholson's nomination. "If we don't have enough there, it's just going to make it worse, and worse and worse."

While campaigning for his second term, Obama promised the war in Afghanistan would end on his watch. At the end of 2014, the White House declared an end to combat operations there. Yet American forces and money remain committed as Afghan troops and police slowly take over the fighting.

The mission of the U.S. troops in Afghanistan is to conduct counterterrorism operations and to train and assist the Afghan security forces. Nicholson assured the Senate Armed Services Committee that if confirmed, he will do a thorough review to make sure there are enough American forces to accomplish both assignments.

Nicholson acknowledged, however, that security conditions are worsening in Afghanistan. The Afghans held their own in 2015 during combat against the insurgency, he said, but are still not self-sustaining. The U.S. continues to provide the bulk of the money to train and equip the Afghan military and police — more than $4.1 billion was allotted in fiscal year 2015 alone to the Afghanistan Security Forces Fund, according to the Defense Department.

"The Taliban came at the (Afghan forces) more intensely than perhaps we anticipated," Nicholson said. "Because of that, we did not make the advances we projected we thought we would make."

Overall, the U.S. has committed $113 billion since 2002 for reconstruction projects in hopes of establishing a stable, functioning Afghan government. Yet, nearly 15 years later, Afghanistan still lacks the capacity to independently operate and maintain the hospitals, roads, power plants, and more built with all the money.


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