My speaking style was criticised by no less an authority than Arnold Schwarzenegger. It was a low moment, my friends, to have my rhetorical skills denounced by a monosyllabic Austrian cyborg.
To say that authority, whether secular or religious, supplies no ground for morality is not to deny the obvious fact that it supplies a sanction.
No oppression is so heavy or lasting as that which is inflicted by the perversion and exorbitance of legal authority.
My speculation is that the U.S. does not want to establish the principle that it has to defer to some higher authority before carrying out the use of violence.