Paz's point of view (the Ultimatum assassin). Word: Question.
He hurled the words at Bourne, desperate for an explanation. "Why didn't you take the shot?" Accusing. He should have taken it; by failing to execute him, Bourne had broken all the unspoken laws of victor and vanquished.
Bourne looked at him, a ghost of laughter, or perhaps pain, in his eyes.
When he responded, his voice was quiet, almost defeated. He asked, "Do you even know why you're supposed to kill me?"
Paz stared, wary, disconcerted.
Good question.