OXNARD, Calif. -- Jason Witten's retirement led some to agonize about a leadership void for this young Cowboys team.Watching Sean Lee adroitly handle the first, tumultuous days of training camp should ease those concerns."Jason always led by example,'' Lee said. "He was a role model for me."He said when you face something, you face it head on.''That's what Lee has done with questions about the national anthem.