BEIJING — When I was at school, sports lessons included an exercise where we threw hand grenades (made from wood topped with metal to resemble the real thing) against a wall over which a red slogan had been stretched offering the reason for such a militaristic pastime: "Exercise our bodies and protect our motherland." We feared that China might be invaded one day by the American "imperialists" or Soviet "revisionists."

Indeed, the whole West held evil intent toward us. Living in a closed country, we had little idea about the outside world.

I went to school in Nanjing in the early '70s, when the revolutionary fever of the Cultural Revolution was calming down. A few years earlier, my father had been banished to the countryside for criticizing the government. My grandfather, a small-time grain dealer, had committed suicide, worried that his not-so- politically-correct background would land him in trouble. These were the darkest of times for my family, and for our nation.