Terna, in America since 1952, isn't trying to be “the conscience of the world,” but said he is concerned by similarities he sees between today's politics and the “narrow nationalism” of the 1930s.
“This anti-Semitism is a problem that the world has to live with. I'm used to it, it's part of my functioning. It's there in the background, all the time,” he told AFP.
Terna was a child in Prague when Nazi Germany annexed parts of Czechoslovakia in late 1938 before overrunning the country the following year as Adolf Hitler began his march through Europe.
All of his family members perished in Nazi killing factories during World War II.
The Auschwitz-Birkenau death camp in Nazi-occupied Poland was the third of four camps that Terna was detained in during the war but he said he bears no hatred despite what he lived through.
Terna, an alias chosen by his father to hide from the Nazis, arrived there in the autumn of 1944 after being held in the Terezin camp, near Prague.
“Auschwitz is not gone. Part of me is still in Auschwitz,” he said, during an interview at his house in Brooklyn.
He wasn't at Auschwitz long. Along with thousands of other men, Terna was dispatched to the Kaufering labor camp in Dachau, Bavaria.
There, detainees were forced to build underground factories that couldn't be detected by Allied bombers.
American forces liberated the camp in April 1945. Terna, extremely weak, returned to Prague to find a Communist official living in his old apartment.
The official insulted him and chased him away.
After some time in France, Terna left with his first wife, now deceased, for a new life in the United States.
“I had the idea of getting as far away from Europe as possible,” he said.
Terna's mind is as sharp as his body is fit.
He climbs the 35 stairs in his home without hesitation and is a prolific painter.
With attacks against Jews in Europe and the United States on the rise, Terna said it is up to the few remaining survivors of the Holocaust to keep a check on anti-Semitism.
“I am one of those leftovers that points a finger at those who are anti-Semites, who try to blame the world's ills on us, us, Jews, today,” he said, surround by brushes and tubs of paint.
He believes that those like him who have testified to the atrocities have done their job.
“Today, you can go anywhere in the world, from here to Tasmania and New Zealand. There isn't a school of higher learning that does not have a course on the Shoah (Hebrew term for 'Holocaust').
“So, in a way we have succeeded,” he said, his accent hinting at his Czech origins.
But he believes there is still work to be done.
Terna frets about the rise of nationalism and division, particularly in Central Europe but also in the United States.
Hungary comes to his mind first, but he said when Donald Trump was elected US president in 2016 he was projected back to 1930s Prague.
“All the signals went up, all the flags went up,” he explained, reminiscing how when the Nazis took over Germany it was all his family could talk about at home.
“My reaction to what is happening now is very much colored by what I experienced in the 1930s. Afraid is the wrong word, but (I'm) very very much concerned,” Terna added.
He believes political, nationalistic and religious divisions can be healed, though. “That we will go back to the awareness that we are all in the same boat. I'm very optimistic about it,” he said.
Terna thinks Merkel's visit to Auschwitz, the third by a German chancellor, can go some way to helping. “It is a healing process of saying we are responsible for each other,” he concluded.