IT MUST be worrying to China’s leadership that some of the largest outbreaks of urban unrest in recent years have occurred in some of the country’s most prosperous cities. The most recent example, in the port city of Ningbo, involved thousands of people facing off with riot police in a protest over plans to expand a chemical factory in the city. After three days of sometimes-violent demonstrations, the city government announced on October 28th that it was halting the project (as the Associated Press reports). For now at least, the protests appear to be subsiding.

They were triggered by the same middle-class fears that inspired large-scale demonstrations in the port cities of Xiamen in 2007 and Dalian last year. All related to projects involving the manufacture of paraxylene, a toxic chemical, which protesters believed would pollute the environment. Ningbo’s, however, were unusual for their violence and their proximity to a political event of huge importance to the Communist Party. On November 8th the party will convene its 18th congress in Beijing. So determined is it to prevent disruption of this event, and of a meeting right after it which will endorse sweeping changes to the country’s leadership, that taxis in Beijing are even said to have been ordered to disable the mechanisms that allow passengers to open rear windows. A Chinese newspaper, the Global Times, says this is because officials do not want people throwing dissident leaflets out of them. (Many drivers have not complied.)

The party is particularly nervous this year as the country’s economic growth slows and members of the new middle class become more anxious about their prospects in the years ahead. Even the official media sometimes hint at this. Another Chinese newspaper, the China Daily, reported recently on a survey of Beijing residents that was conducted by a government-sponsored think-tank in the capital. Only 1% of respondents said their quality of life had greatly improved in recent years, while one-fifth said it had improved slightly. More than one-third said they felt no change, and more than 40% said their lives were worse.

Even the state broadcaster, CCTV, has offered a rare hint that the party’s efforts to portray a country of growing happiness are being greeted by some with cynicism. Beginning in late September it broadcast a series of programmes called “Reaching the grass-roots: people’s voices from within”. Ministry of Tofu, a blog about Chinese society, reported that producers of the series must have been somewhat disappointed if they expected their interviewees, who were asked how happy they were, to gush with satisfaction. Many dodged the question and some gave answers that were nonsensical or funny.