Afghanistan needs foreign soldiers for years: Dunford
The assertion comes amid intense debates about how many troops the United States and its mainly NATO allies should leave behind to conduct training, support and counter-terror operations post-2014.
However, the White House favours about 7,000 US troops, but some in the US military would prefer two or three times as many.
Dunford would not be drawn on how many he thought should remain, referring instead to "sustainability".
In an interview with Reuters on Tuesday he argued for a significant presence after the US-dominated International Security Assistance Force (ISAF) is disbanded next year.
"The post-2014 presence is a lot more complicated than the numbers and the numbers have become a distraction, to be honest with you," Dunford said in his Kabul headquarters.
"It's about a lot more than numbers. It's about what capability is required to sustain the Afghan security forces after 2014," he said.
ISAF currently numbers about 87,000 troops, three-quarters of them American. Dunford said the intense debate about the size of the residual force was not helpful.
One of the sticking points about that force has been the suspension of talks between Afghanistan and the United States over a bilateral security pact to replace the ISAF mission.
The pact talks were suspended in June amid Afghan anger over the opening of a Taliban office in Qatar, which President Hamid Karzai's government blamed partly on US involvement.
Dunford said he had talked "at every level from district and province to members of parliament ... to President Karzai" and was adamant the pact would be signed.
He also said it was too early to judge whether the mission in Afghanistan had been successful, or how America's longest war would be remembered.
"Our objective is a stable, secure and unified Afghanistan. And we're still working towards that end," Dunford said."And if we achieve the objective ... I think it will be remembered as being successful.
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