"Have you planned for a reduction in force?" Nealin asked bluntly.
Hagel said if the $52 billion cut remains in place, "there will be further cuts in personnel, make no mistake about that."
"I don't have any choice," he said.
The spending cuts this year may feel more dramatic than in times past because of a vast growth in Defense Department personnel and equipment costs over the past decade, said Todd Harrison, a senior fellow at the Center for Strategic and Budgetary Assessments in Washington. But current spending levels are close to what they were in 2007, when the war in Iraq was at its peak.
"So we're not even back to a pre-9/11 level," he said.
Since 2000, the number of U.S. troops has grown by about 3 percent to fight the wars in Iraq and Afghanistan, Harrison said. But the number of civilian Defense employees hired to support the troops has far surpassed that, growing by 14 percent in the same time.
Hagel said he is taking a hard look at where fat can be trimmed from the Pentagon and said the military has been "guilty of wasting a lot of money on a lot of things." But he also said he "can't lead this institution based on hope, based on I think, or based on maybe" - and predicted more dollar cuts ahead.
In Charleston, where the hopeful crowd quickly turned worried, Sandra Walker pointedly asked Hagel what might be in store for her job security, retirement benefits and security clearances if the shortfalls continue.
"I've taken a second job to compensate, because I have several children at home," said Walker, who works in education and training at a medical clinic on base. "And if we are going to have future furloughs, will those things be taken into consideration for the future of our jobs?"
Sticking to his message, and stopping short of directly answering her question, Hagel offered little hope.
"There's no good news," he said.