A crowd waves Turkish flags at a rally on Saturday in Istanbul commemorating the first anniversary of a failed coup against the government. (Ozan Kose/AFP via Getty Images)

Turkish President Recep Tayyip Erdogan on Saturday used the first anniversary of a coup attempt against his government to accuse his main political opponent of treason and portray civilian resistance to the plot as a triumph of the Muslim faithful.

Erdogan’s fiery speech before a huge crowd in Istanbul highlighted the lingering trauma of the failed coup, which killed 250 people over the course of a terrifying night and day of violence.

The speech also showed how the events have become an increasingly important political cudgel for the president and his Islamist supporters, with the victory over the coup plotters seen as a critical part of the government’s popular mandate.

The government has blamed the coup attempt on loyalists of Fethullah Gulen, a Turkish cleric who lives in exile in Pennsylvania.

On that night, authorities said, renegade soldiers loyal to Gulen used tanks, planes and helicopters to occupy or attack television stations and public buildings, including parliament, and were defeated after Erdogan rallied citizens to the streets.

The events provided at least a momentary sense of unity in polarized Turkey: a shared shock and revulsion at the willingness of soldiers to crush people under armored vehicles and strafe crowds from the air with cannon fire.

That unity, though, has dissipated as the government cast a wide net in pursuit of its enemies, sweeping up the failed coup’s alleged accomplices but also dissidents.

The still-murky background to the coup attempt and the staggering number of people caught up in the ensuing crackdown have fueled the apprehension. About 150,000 people have been dismissed or suspended from their jobs, and 50,000 have been arrested.

A state of emergency that gives the government extraordinary powers has remained in effect for almost a year, prompting critics to charge that Erdogan seized on the coup attempt to bolster his power.

[As Erdogan gains power in Turkey, a weakened opposition tries to stand in his way]

The president has argued that Turkey is united and that the events of that night clarified the line between loyalty and sedition.

The commemorative events on Saturday, planned in meticulous detail by the government, seemed designed to convey the sense of a national coming-together.

The country was blanketed by posters depicting scenes from the failed coup in the manner of epic paintings. Public transportation and cellphone services were provided free of charge. Photo exhibits were set up in public squares, narrating the chilling sequence of events.

“Today is the day the country was saved,” Ibrahim Agagul said as he looked at the pictures Saturday outside an Istanbul municipal building where 20 people were killed. “Today, the people wrote a saga.”

In his speech, Erdogan focused on the notion of shared sacrifice. “The treachery we face makes us stronger,” he said, speaking at a bridge that was the scene of major clashes during the July 2016 violence.

His most pointed comments were a response to statements made this year by Kemal Kilicdaroglu, the leader of the main opposition party, suggesting that the coup had unfolded with the government’s knowledge. Over the past few weeks, Kilicdaroglu led a 260-mile march that was an effort to highlight the purge by the authorities.

“You should be ashamed of yourself,” Erdogan said of Kilicdaroglu. “This nation is not a coward like you. This nation has a heart.”

Read more:

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Turkey’s opposition stages massive rally in a show of strength against Erdogan

March for ‘justice’ by Erdogan opponents in Turkey gains momentum and alarms government

Today’s coverage from Post correspondents around the world

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