Long term (50-100 years) the growth of the Chinese economy will be determined by the amount of political and economic freedom in China (again, IMO).
China will prosper as long she has political STABILITY and economic freedom. China had an American style republic in 1911 and it failed because entrenched interests used the democratic process to stifle reforms and created family monopolies. China needs a large educated and sophisticated middle class to have democracy. The Chinese needs to develop a loyalty to national interest over loyalty to family/clique interests. Today 90 percent of China are rural farmers or poor factory workers who resent the urban rich. Democracy will mean the return of Maoist government. Just look at Venezuala and the Gaza strip.