Even today the European Union is considered more successful in terms of economics than politics, because its member states still differ on many issues. The problem of how essentially Christian Europe will accept Muslim migrants remains unsolved.

There is a vital lesson for China in all this. The terrorist attacks in the Xinjiang Uygur autonomous region show that some of them disown their national identity as Chinese citizens.

This is dangerous, for being residents of the northwestern border region, they can mobilize to attack local residents, even join the Jihad.

True Islam, however, is tolerant and pluralistic in nature. Islam is compatible with modern values and there is no reason for the two to be separated.

The culture in Xinjiang is special, a cohesive mix of Islamic and ethnic Uygur cultures. The authorities, therefore, have to help local people stay away from extremism by better integrating them into society. To treat terrorism as a kind of "clash of civilizations" will only weaken the fight against terrorism.

The author is a professor at Johns Hopkins University-Nanjing University Center for Chinese and American Studies.