EAST WINDSOR, N.J. — The gas masks given to me and other Soviet first graders in 1987 were hand-me-downs from World War II, made of stiff rubber and too big for our faces. They trapped moisture and reduced the world to two blurry circles bouncing in front of my face. Our teacher didn’t tell us about the gas mask drill ahead of time — she simply handed out the masks, and we blindly paraded around the school before going back to our lessons. None of us bothered to ask why we were training. There was no need.

By the time my classmates and I entered first grade, we already knew that the United States and its Western allies were planning to harm us, the children of School No. 3 in Kharkiv, Ukraine. The only thing left to do was to put on the gas masks.

The impending Capitalist attack was just one of countless threats a Soviet child had to be prepared for, even in the waning years of the Soviet Union. There were the standard rules for surviving a dictatorship: Don’t trust anyone but family, never attract the attention of the police, always be patriotic. There were rules that applied only to Jews: Don’t utter words like “synagogue” in public, don’t share family stories with non-Jewish neighbors. Anti-Semitism waxed in accord with overall social anxiety; by 1989, it led my family and thousands of others to flee.

Myriad don’ts permeated Soviet life. There was little difference between dangers visible and invisible, real and superstitious. Play with a knife and you’ll get cut; hand a friend a knife instead of placing it down on the table for him to pick up, and your friendship will wither. You were exposed and vulnerable in public, in your apartment, in your head. The evils, the omens, the Americans working on secret weapons and the K.G.B. looking for traitors were all part of the same malevolent atmosphere.