Perry, the Texas governor, said that Pakistan had shown the world that "they can't be trusted."
Perry has called for a total reevaluation of American foreign aid, saying he would "zero out" all assistance to other countries, even Israel, before setting new aid levels.
Bachmann, a member of the House Intelligence Committee, said in response that you "have to recognize what's happening on the ground."
"They certainly aren't looking out for the best interests of the United States. I wouldn't expect them to. But at the same time we have to have our interest, which is national security, represented," she said. "The best way we can do that with an uneven actor state is to have some sort of presence there."
Mitt Romney agreed, saying that the United States must be engaged with the broader region.
"We can't just write off a major part of the world," he said. "We don't want to literally pull up stakes and run out of town, after the extraordinary investment that we've made. ... We need to bring Pakistan into the 21st century -- or the 20th century, for that matter."
That also means the U.S. must ensure that Afghanistan does not become a "launching point for terror," he said.
Jon Huntsman Jr. said the United States had achieved some major goals there, and needed to draw down its military presence.
"We do need intelligence gathering, no doubt about that, we need a strong special-forces presence, we need a drone presence, and we need some ongoing training of the Afghan National Army, but we haven't done a very good job defining and articulating what the end point is in Afghanistan," he said. "I think the American people are getting very tired about where we find ourselves today."
Romney said he would listen to the advice of commanders on the ground. Huntsman replied, "The president of the United States is commander in chief."