What number should replace the X to the magic square?

A judge grew tired of seeing the same town drunk in front of his bench. One day the judge glared down at the man, who was still intoxicated, and thundered "It is the sentence of this court that you be taken from here to a place of execution and there hanged by the neck until DEAD."
The drunk promptly fainted.
The court bailiff commenced to reviving the man, and looked up at the judge, at which time the judge shrugged and responded "I've always wanted to do that."