There are over a billion Muslims in the world. Many of them can and do live peaceably in liberal, secularized societies--but not all, as evidenced by the Boston Marathon bombings, the Fort Hood shooting, the Pulse Nightclub shooting, and the San Bernadino shooting.

The United States faces less Islamist terrorism than Europe or the Middle East, not only because the US has a much smaller Muslim population and significant barriers to immigration, but also because American Muslims (with certain noted exceptions) tend to be more likely to accept liberalized values than Muslims elsewhere in the world.

Two reason the US is different than China. One the US social political structure makes is very hard for religious zealots to gain control. Note how hard the Dominionist Christians have been trying for the last 100 years. Their political wins have failed to deliver completely on a societal basis.

Second reason Muslims in the US generally hate Salafism and Wahhabism.

China on the other hand isn't going to let Saudi Arabia engineer a Wahhabi led revolt in western China.

Are you ok? Where did the parent say anything about the United States?