A top, secular Middle Eastern intel analyst with an Istanbul front seat view to the coup clarified the internal political context even before the - widely expected - proclamation of a state of emergency (if France can do it, why not Turkey?):
"They knew five to six hours beforehand that a coup was in the works and let it go ahead, knowing, as they must have, that it would fail... This affair has propelled Erdogan to semi-divine status among his supporters. The way is clear for him to get what he wants, which will be a powerful presidency and removal of the secularism principle in the constitution. This would set the stage for the introduction of aspects of Sharia law. He tried this in the early years of the AKP government with the introduction of Zina, a strictly Islamic provision, which would have criminalized adultery and could have opened the door to the criminalization of other islamically illicit sexual relations as Zina is about this in general and not just adultery. But when the EU objected he backed off".
Comment: See also: US will continue bombing Manbij despite massive civilian casualties