THE top of the carrot, blackened by frost, poked just above the frozen ground. As soon as he saw it, Harry Wu dropped to his knees and scraped for it until his fingers bled. After 18 months in one of China’s laogai (“re-education through labour”) camps, hunger consumed him. Already he had sampled the half-rotten roots of cabbages left in the ground, and learned to dig into rat-holes to find stores of grain. In another hole he found a tangle of hibernating snakes, pulled them out, bit off their heads, skinned them and boiled them up for that wonderful, near-forgotten taste of meat.

He had learned to fight, too. When he took off his glasses he no longer looked like the intellectual he was. He was ready to beat up anyone who challenged his theft of a hard wotou bun or a piece of salted turnip, aiming his punch straight for the nose or the eyes so that his assailant wouldn’t try twice. The camp had made an animal of him, throwing desperate creatures together as, when a boy, he had put ferocious yellow ants and black ants in a bottle and watched them kill each other. In his case, his fall into barbarity had not taken long.

The ostensible reason he was there—he assumed, for he was forced to sign the charge-sheet in 1960 without reading it—was because he had been accused of stealing 50 yuan. In fact he had been hauled in to be turned into “a new socialist person”. As an eager student at the Geology Institute in Shanghai in the mid-1950s, after the Communists had seized power, he resented spending half the day studying party doctrine. He was slow to confess in public that, as the son of a banker, waited on by servants and educated by Jesuits, he was from “the exploiting class”. He had also skipped indoctrination sessions to be with his girlfriend. The result was that his brain had to be dulled by hard labour, and new thoughts put inside.

This went on for two decades, all through his best young years. He worked on farms and down a coal mine, where his back was broken. The Red Brigades found his favourite books—“Moby-Dick” and “The Old Man and the Sea”, sagas of men obsessed with a dream against enormous odds—and burned them. For a week he was put in solitary, in a cement cell three feet high. He had tried to send out letters of protest, desperate that no one knew of his plight or where he was. As comrades died around him, he reflected that their lives were just a flick of cigarette ash on the wind. When he had clambered out of that mood, he resolved not only to survive but also to ensure that no one forgot China’s laogai and the thousands suffering there.

This was harder than he imagined. After years of rising slowly through the prisoner hierarchy, helped too by the death of Mao Zedong and the milder rule of Deng Xiaoping, he emerged to try to work as a lecturer in geology. He was still viewed as a rightist, he found. And China remained indifferent to the laogai, with a further twist: the forced labour of prisoners was enabling his country to roar into world markets as a producer of cheap car parts, tools, toys, clothes and hardware. The prison camps were being renamed factories, and the world hoodwinked into buying goods stained with blood and marked with tears. As soon as he could get his papers, in 1985, Mr Wu left for California—to make a new life, and spread the word.

Making trouble

He had $40 in his pocket, supplemented by night shifts on a doughnut stand. His English was fractured and, again, his voice was a lonely one. Americans in the mid-1980s knew almost nothing of mainland China except, increasingly, its trade potential. Stories of the Chinese gulag were the province of right-wing think-tanks, such as the Hoover Institution, and right-wing congressmen. Many thought he was exaggerating the horrors, or being soft on criminals who deserved it. But Mr Wu stressed that China’s labour camps were both inhuman, and contained an alarming number of political troublemakers like himself. Besides, America, like most European countries, already had laws on the books banning the import of goods made with forced labour.

To get his point across, he travelled the world with instruments of torture in his suitcase. Relentless as a terrier, he lectured, lobbied and wrote, until by 1989—when Tiananmen Square made his argument for him—Americans did not question that the gulag existed. What he most yearned to do, however, was to go back to China for more evidence. In the early 1990s he managed to sneak in several times, with journalists and hidden cameras, to the camps where he had been held. With fame, his trips became much riskier: he was chased by security men, spotted from watch-towers, and in 1995 was arrested as he tried to enter from Kazakhstan. Only pressure from the Clintons (Hillary being about to visit) secured his deportation, after 66 days.

That second spell of captivity, though relatively gentle, reminded him how much he had been shaped by the first. He could fall asleep anywhere in 15 seconds, even with guards watching, and still be aware of what was happening round him. He could see escape routes where others couldn’t. His broken back still ached, and the sight of prisoners made him tremble so much that he could not film them. None of this, however, curbed the overwhelming hunger the laogai had left in him: hunger to play with fire, taunt the system, dig deep.