AT RARE moments the future of a nation, even one teeming with 1.3 billion souls, can be bound up in the fate of a single person. Just possibly China is living through one of those moments and Chen Guangcheng is that person. A blind activist from Shandong province, Mr Chen emerged from poverty, fought for justice and paid the price with his own liberty. Last month he made a bid for freedom and became ensnared in the impersonal machinery of superpower politics. What now befalls him and his family raises questions about Sino-American relations and the character of Chinese power.

In many ways, Mr Chen is the best of modern China. Blind since childhood, poorly educated until adulthood and then self-taught, he became a lawyer, never a safe career in a country where might is right. As a peasant activist fighting local battles—which makes him a much more potent force in China than politicised members of the urban elite such as the artist Ai Weiwei (see article)—he was praised for years by the local government for advocating the rights of disabled people. Then he crossed the line by taking on the local party over the abortions and sterilisations it enforced as part of China's strict one-child policy. After four years in jail on spurious charges, Mr Chen was kept prisoner in his own home for 19 months.

On April 22nd he fled to the American embassy in Beijing, where Hillary Clinton, America's secretary of state, was due to arrive for her country's annual Strategic and Economic Dialogue with China. What happened next is disputed (see article). American diplomats say they became close to Mr Chen, even holding his hand when they spoke. They say that, after six days inside, Mr Chen willingly left the embassy for hospital, accompanied by the ambassador, to be reunited with his family. He had received assurances from the Chinese government that he would be treated well and allowed to study law at university. However, from his hospital bed, a weary, browbeaten Mr Chen suddenly began to complain that American diplomats had “lobbied” him to leave, that they had not let him confer with his friends and that Chinese officials had threatened his wife. He was “very disappointed” in the American government and said he wanted to leave China. For their part, Chinese officials acknowledge no deal—but they have sternly demanded an apology from America.

The Beijing switch

With luck the dispute will calm down. Perhaps Mr Chen will be spirited away to America, or find a way to live normally in China. But the incident raises three questions. Most immediately, did America's best diplomats let a brave man down? With Mr Chen out of their care, they now have little bargaining power. If they were duped by their Chinese counterparts, or too ready to accept their assurances, they will be taken as fools. If they struck a deal in haste, calculating that currencies and tariffs should eclipse the rights of an inconvenient blind man, they will be taken as knaves. Mrs Clinton boasted that Mr Chen left the embassy “in a way that reflected his choices and our values”. Her words will undoubtedly be scrutinised in this year's election.

Yet the plight of Mr Chen raises two deeper questions about his own country. The first is whether China still feels it must put its relations with America before anything else. In past disputes, notably the aerial collision of a Chinese fighter and an American spyplane in 2001, China has tended eventually to put America first—as the source of trade and wealth and the policeman for the global commons. But China is stronger now, its economy is bigger, it can defend its own shores and it expects to carry weight in the world—especially as, in the view of some triumphalists in Beijing, America has been dragged down by the financial crash and its vicious partisan politics.

If Mr Chen is now punished and Barack Obama is humiliated, that will signal a troubling shift in the terms of the superpowers' relations. A wounded, suspicious America and a rampant China, bent on winning the respect it thinks its due, set the stage for dysfunction at best and conflict at worst. It would be a terrible outcome for both superpowers and for the world. They should strive to patch things up.

The power shift

The other question—and one that will preoccupy China in a year when power shifts to the next generation of leaders—is how the country is run. The blind lawyer in dark glasses is just one of millions of ordinary people smarting under arbitrary rule. For a long time—first when China shed Maoism and then as its economy surged—most Chinese people cared less about the niceties of the law than their fast-rising living standards. Even then the weak, the disabled, the unemployed and the poor were ignored, sidelined and sometimes trampled in the rush for wealth. Now, a slowing economy, corruption, rural anger and urban freedoms all mean that the party is under pressure to enforce the rule of law—especially in order to curtail the impunity of local officials.

The Communist Party recognises that it must start to be more accountable and give people a legal outlet for their grievances. Faced with an insurrection in Wukan, after villagers protested about local officials' profiteering from the sale of land, Beijing ended up siding with the villagers. The party has been keen to depict the sacking of Bo Xilai, who ran the south-western region of Chongqing, as proof that China is a country of laws. Wen Jiabao, China's prime minister, has argued that corruption will not be tolerated. Try as it might, the party cannot altogether control the country's 250m microbloggers who follow each drama live and continue to confound the censors.

The dilemma is that although the party needs the law to govern, it cannot submit to the law without losing power and giving up privileges. At the moment the party still wants to have it both ways. More than any other incident so far, the disturbing case of Mr Chen raises doubts about whether it can. It is a heavy burden to be resting on the frail shoulders of a man lying in a Beijing hospital bed as the diplomats and politicians dine together a few blocks away. But it matters enormously to China's future.