Stamina. There is a greater physical element to this job than you would think, just being able to grind it out. And I think your ability to not just mentally and emotionally, but physically be able to say, "We got this. We're going to be OK.
Here at home, we will strengthen our defenses but not succumb to a siege mentality that sacrifices the open society and liberties and values that we cherish as Americans, because great and proud nations don't hunker down and hide behind walls of suspicion and mistrust.