On Sunday, Colorado Governor John Hickenlooper joined with voices calling the clinic shooting an act of “terrorism.” This comes as a new study finds white Americans are the biggest terror threat in the United States. The New America Foundation says that of 26 acts of terrorism in the U.S. since 9/11, most were carried out by whites. The list does not include several mass shootings carried out by whites, including Sandy Hook or the Aurora movie theater, because they lacked political motivation.