The resignation of Ahmet Davutoğlu as Turkey’s prime minister makes clear that opposition to Recep Tayyip Erdoğan’s personal ambitions has reached the very top of the ruling Justice and Development Party (AKP).

Davutoğlu announced on Thursday that he would step down later in May, when a party congress is due to name his successor.

Although the former diplomat did not criticize Erdoğan on his way out — “Nobody can hear a negative word from me about the president,” he said — his doubts about Erdoğan’s plan to transform the presidency into an American-style executive were widely reported and broadly shared.

Davutoğlu’s objections were more than theoretical; a presidential system would have made the prime ministership, and hence Davutoğlu, powerless.

Power struggle

The two men started to fall out after Erdoğan moved to the presidency in 2014. Leaked documents reveal they sparred on everything from talks with the European Union and Kurdish separatists to the appointment of a central bank governor.

The core issue was always the same: Erdoğan felt his underling claimed too much independence while Davutoğlu argued he was only carrying out his constitutional duties.

Last summer’s elections heralded a breaking point. When the AKP lost its parliamentary majority, Davutoğlu called for a coalition with the right-wing Nationalist Movement Party — which would have curtailed Erdoğan’s power and made the prime minister a more central figure.

Erdoğan vetoed the proposal. He called new elections instead and ended up winning back a majority for the AKP, if not the two-thirds majority needed to rewrite the Constitution on his own terms.

Ambitions

Turkey expert Steven A. Cook, a senior fellow at the Council on Foreign Relations, predicted in The American Interest at the time that Davutoğlu would end up on the losing side.

“Erdoğan is, and will likely remain, the sun around which Turkish politics revolves,” he wrote.

The former only tapped Davutoğlu as his prime minister because he seemed to pose no political threat.

When Davutoğlu decided he wanted to be more than Erdoğan’s yes-man, his fate was sealed.

Davutoğlu launched anti-corruption reforms and let it be known, according to Cook, that he would have no objection if the supreme court tried four former cabinet ministers and Erdoğan allies.

Erdoğan nipped both initiatives, which threatened his patronage network, in the bud.

Liability

The fact that Davutoğlu even tried, though, suggested it was dawning on the AKP leadership that their boss had become a liability.

Bullying the country’s central bankers, locking up journalists, undermining checks and balances and destroying relationships with important countries may have political benefits at home, but it is not cost free.

Erdoğan is supported almost unquestionably by half the country. The other half sees him as little better than a dictator.

As long as Turkey remains so starkly polarized, it will struggle to revitalize its economy and repair its relations with other nations.

Many AKP leaders recognize as much. Two of the party’s co-founders, Bülent Arınç and Abdullah Gül, both resisted Erdoğan and ended up outside government. Davutoğlu now joins their ranks.

Erdoğan’s solution is always to punish dissent. He never budges, there can never be compromise. It’s an instinct that allows him to project a strongman image many Turks clearly like. But it is also isolating him anyone who dares think independent thoughts, including his once closest allies.

At some point he is going to run out of acolytes to fire.