China does read its own history and understands that the Ming Dynasty (In many ways the "Ideal" Dynasty of China) started out as a peasant revolt against the Yuan (Mongol) Dynasty.
More on the Ming Dynasty:
http://en.wikipedia.org/wiki/Ming_DynastyChina has a long history of other peasant revolts, in fact the Communist take over of China was less a "Marxist" revolution then a traditional Peasant revolt.
Right now, the rural areas of China has been ignored since the 1980s, prior to the 1980s rural areas prospered (We will ignore the "Great Leap Forward" which was a disaster for both rural and urban areas and done more so that Mao could regain lost power then anything else). Thus in the 1950s you saw the takeover of lands from landlords and turning those lands over to the peasants who actually worked the fields. This increased food production (Notice this was the OPPOSITE of the collectivism program Stalin had done in the Soviet Union). Rural China boomed in the 1950s, 1960s and 1970s, but then in the 1980s China old Leadership slowly gave way to a new generation of the Children of the leaders of the Communist Rebellion of the 1920s to the 1940s. This new set of leadership jumped at the chance at "Modernization" which permitted them to become rich. This wealth was mostly along the coast with easy access to overseas markets. At the same time Rural China went down hill, the State STOP many of the programs to help the peasants AND many of the local Communist party leaders saw what was going on along the Coast and thought they should ALSO get "Rich" but this time on the back of the peasants. Education, Medical and health funding in Rural China declined do to this new generation of leaders wanting to equal what other young leaders of China was getting on the coast.
While Rural China went down hill, Urban China boomed but only along the coast. In this Boom the desire to maximize profits came out on top EVEN IF THAT MEANS NOT PAYING WORKERS, LEAVING SUCH WORKERS WORK IN TERRIBLE CONDITIONS ETC. This worked OK, as long as employment existed, but when the economy went down hill starting in 2008, these marginal persons lost what security they had when unemployment went up (Remember China does NOT have unemployment insurance).
Now, Karl Marx in his works made several errors, but one thing he did note and has been found to be correct is the observation that Revolutions do NOT occur as things go down hill, but only after things bottom out and the economy is starting to boom. CIA even follows this observation, it has been found to be that accurate. Thus the time to worry about a revolution is NOT as things go down hill, but as it bottoms out and starts to rebound. The Great Famine of 1785-1787 was over by the time of the French Revolution of 1789. Both Russian Revolutions occurred in 1917, while the worse year of the war for the Czar had been 1916, the German Revolution of 1919 occurred only after WWI ended in 1918.
Now while things went down hill you had protests, for example the German Mutiny of its Fleet in 1918 (While WWI was still going on) but they are signs of trouble (In fact both Britain and France had massive strikes in 1918 and do to the fear of how those strikes were "resolved" were more the eager to sign a peace treaty with Germany in 1918, they saw themselves in the same position as Russian had been in 1916 and Germany in 1918 so wanted to end WWI as soon as possible).
In regards to China, WWII saw massive parts of China occupied by Japan. Only when Japan was defeated then the pre-existing Communist party was able to lead a revolt. This appears to be the case right now in China, China is in a classic pre-revolutionary status in both Rural and Urban China. The peasants want change and if forced will revolt. This time maybe with a true Marxist revolt (Through I suspect a more peasant/urban worker revolt). Do to this fear China does NOT want to touch it off, China wants to endure the unrest and make sure NOTHING unites the lower classes against the present Chinese's Government. A massacre like you suggest would unite the peasants and lead to a major revolt. China can defeat such a revolt, as it did in the 1800s, but the cost of such suppression was to make the lower classes even more united and demanding reforms, those demands lead to the Revolution of 1912 and then again in the Communist Take over in 1949. We may see something similar again.