The reason to do it is when you want to prove that you have the power to get away with that or anything else. It’s called intimidation (aka, the Chicago Way). See also, the Overton Window.
I can’t believe I am agreeing with Obama, but when an amercian citizen joins the enemy then he become... THE ENEMY and you can kill him any time you want
What I DO object to is the media hypocracy- if this was Bush, they would be demanding impeachment.
Our intelligence finds a building filled with terrorists. We determine that American citizen Jihadi Bob is in the building. Well, the only thing to do is first send out a team of lawyers and legal advisors to inform Bob of his rights before we send in the missile. Yeah, that would be the correct thing to do. (snicker)
Possibly.
A very similar question is...
Is there ever a good reason to kill American citizens without due process?
Citizenship means nothing to terrorists. Due process for terrorists consists of whatever process is required to exterminate them and anyone found with them.