SÃO PAULO, Brazil — Jair Bolsonaro, an ultraright wing populist , was elected president on Sunday . As I processed this new reality, I looked out my window and watched the celebratory fireworks illuminate the night sky. In the distance, I made out one of Mr. Bolsonaro's supporters holding up a sign that said, “ Ustra Lives.”

It was a chilling reminder of our past. From 1970 to 1974, Carlos Alberto Brilhante Ustra was the head of the DOI-CODI, the intelligence agency responsible for stamping out critics during military rule. He oversaw the torture of political dissidents while they were detained by the secret police.

Mr. Bolsonaro’s rise has been driven by people’s anger and disillusionment, stemming from a huge multiyear corruption probe that has upended the country, a homicide rate that is sky high and a flailing economy. It didn’t matter to many that his inflammatory rhetoric denigrated women, as well as gay, black and indigenous people, or that he spoke fondly of torture and dictatorships. Indeed, an estimated 43 percent of the population is in favor of the military intervening in government affairs. I think Brazilians have forgotten what it means to be ruled at gunpoint.

My father was a congressman for the State of São Paulo and a socialist. The military junta revoked his mandate after the 1964 coup d’état, and he went back to work as a civil engineer. I was 11 when he was arrested, along with my mother and my sister. It was a sunny morning in January in Rio de Janeiro in 1971, and we were getting ready to go to Leblon beach, which was across the street from our house. Suddenly, six armed men dressed in plain clothes entered through the back door into the kitchen, pointing machine guns. Outside, more men surrounded the house.