THESE are worrisome times for China's rulers. The Communist
Party's credibility was already damaged by a collision of two
high-speed trains on July 23rd that left 40 people dead and
prompted even the state-supervised media to indulge in a rare
outcry about official disregard for public safety. Now comes a
demonstration in the north-eastern city of Dalian that has
prompted a remarkable climb-down by the authorities. On August
8th a storm smashed through the protecting wall of a paraxylene
(PX) factory in the city. To Chinese environmentalists PX, a
chemical used to make polyester, is synonymous with toxicity.
Around 12,000 people joined the protest demanding the plant's
closure. Demonstrations of this size are exceptional in China's
boomtowns.  So too are immediate capitulations. The protest was
generally orderly (the worst violence reported was a few plastic
water bottles thrown at riot police). But its mobilisation
without clear leadership, with the help only of mobile
telephones and the internet, must have