" ... Why would the administration attempt to deceive the world about a terror attack? ... "
The success of the attack was probably due to incompetence on the part of the administration. But, the lie was an attempt to 'use the crisis' for an agenda.
Just as Fast & Furious was devised to aid in passage of the U.N. small arms treaty, a direct impediment to our 2nd Amendment ... this lie was to engender support for the U.N. resolution to ban speech seen as 'offensive' by Muslims, in conflict with our 1st Amendment.
This President has never seen much value in honoring his oath to defend our Constitution.