(CNN) How Joe Biden and his team decided to kill the world’s most wanted terrorist.

I am of two minds about this. It is an impressive achievement of technology and intelligence. I probably would have pressed the button myself. Yet there is an argument of some force that it would have been more effective counter-terror to let him live:

• Zawahiri was in ill health and immobile.
• Ill health deprives one of ingenuity.
• Immobility facilitates contact tracing and bugging.
• He was an unpopular, uncharismatic leader, a factor in Al Qaeda’s relative inactivity.
• He will be replaced; the role is now looking for an actor.
• The replacement may have none of Zawahiri’s impediments.

See Baghdadi Dead; the Role Looking for an Actor.