The highest-ranking officer in the U.S. military stopped in Central Pennsylvania Thursday.

Admiral Michael Mullen spoke to a crowded Capitol Theater in downtown Chambersburg.

Mullen is the chariman of the Joint Chiefs of Staff.

He said supporting veterans and military families should be a top priority for America's communities.

He also said the veterans of Iraq and Afghanistan will make decades of positive contributions to their hometowns.

"They are determined, they are going to live full lives, they're going to make a difference," Mullen said. "And this is a young generation that is geared and wired to serve and make a difference."

Admiral Mullen said it's crucial to make sure Afghanistan does not become a haven for terrorists again.

He also called America's mounting debt the "biggest threat to national security."