It was also slightly reassuring that Mr. Erdogan, stung by the March 31 loss in a city he once led as mayor and upon which he built his political powerhouse, the Justice and Development Party, or AKP, this time acknowledged defeat and did not resort to any more trickery.
Now the question is how Mr. Erdogan will respond to the setback. After the 2016 failed coup attempt against him, Mr. Erdogan wielded ever-harsher political repression. The Istanbul vote should bring him up short and cause him — and his supporters — to ask whether they have created a viable path for the future. It seems voters are signaling they have not.
Mr. Erdogan can turn a corner by ceasing the massive and unjustified prosecution of civil society that he instigated in a hunt for followers of the cleric Fethullah Gulen, whose movement Mr. Erdogan has accused of fomenting the coup attempt, which Mr. Gulen denies. That purge has resulted in 319 journalists arrested, 6,021 academics losing their posts and 4,463 judges and prosecutors being dismissed, not to mention tens of thousands of teachers and government workers who have lost jobs or been investigated. Turkey’s democracy is not dead, but it is still on life support.
Mr. Erdogan could make a fresh start by halting the trial underway of 16 civil-society activists accused of instigating the 2013 Gezi Park protests in Istanbul’s Taksim Square, demonstrations initially against development that turned into a nationwide cause. The prosecution of the activists is misguided and a reflection of Mr. Erdogan’s increasingly paranoid style, transforming the criminal-justice system into a tool of repression.
Mr. Erdogan also faces formidable economic woes, caused in part by Turkey taking on too much debt; he has intensified economic uncertainty and eroded business confidence. Meanwhile, a collision looms with the United States over Mr. Erdogan’s determination to receive the Russian-built S-400 air defense system as soon as next month, a system that is incompatible with NATO’s air defense networks and could compromise the F-35 stealth fighter program. Mr. Erdogan seems to think, improbably, that he can squirm out of this jam by talking to President Trump at the Group of 20 summit. If he cannot, he will probably lose the F-35s and also be vulnerable to sanctions.
A dead end lies that way. The Istanbul election gives Turkey’s president a chance to pick a different route.