In the beginning, nearly 14 years ago, Recep Tayyip Erdogan chose a team of smart and qualified people to run Turkey with him. He now appears set to force out one of the last of that group — Prime Minister Ahmet Davutoglu — and replace him with someone more pliant. This is disastrous for Turkey, as financial markets have recognized.

To know why, look at the issues over which Erdogan and Davutoglu — who is no rebel or hero of a Turkish secular democracy — have sparred, fraying what was once the tightest and subservient of political relationships to breaking point.

The earliest split came soon after Davutoglu's appointment as prime minister, when he proposed an anti-corruption package in response to allegations of corruption made against Erdogan's family and closest political allies. Erdogan said the idea was premature and it was dropped.