FORT HOOD, Texas—If Nidal Hasan plans to welcome a death sentence as a pathway to martyrdom, the rules of military justice won't let him go down without a fight—whether he likes it or not. The Army psychiatrist was sentenced Wednesday to die for the 2009 Fort Hood shooting rampage that killed 13 people and wounded more than 30. But before an execution date is set, Hasan faces years, if not decades, of appeals. And this time, he won't be allowed to represent himself. "If he really wants the death penalty, the appeals process won't let it happen for a very...