BEIJING — In the fall of 2008, dozens of activists secretly worked to produce a political manifesto. It was only 3,554 Chinese characters long, but it listed a series of demands on China’s leaders to make the country a liberal democracy.

Less than a decade later, one of the main authors, the Nobel Peace Prize winner Liu Xiaobo, is confined in a hospital, released from prison though not from custody, to be treated for what his lawyers described as an advanced case of liver cancer.

Mr. Liu’s imprisonment and now his illness have become a grim reflection of the fate of that cause, one born in hope but crushed by China’s intolerance of dissent — and the world’s increasing resignation, even acquiescence, to it, given the country’s diplomatic and economic clout.

The document was called Charter 08 and was modeled after one published by dissidents in Czechoslovakia under Communist rule, Charter 77. More than 300 activists in China signed at first — and many more did later, inside and outside of the country.