According to the Congressional Research Service ’s study , '' American Jihadist Terrorism : Combatting a Complex Threat , '' between May 2009 and November 2010 , law enforcement made arrests related to 22 homegrown jihadist-inspired terror plots by American citizens or legal residents of the U.S . This is a significant increase over the 21 plots caught in the seven interim years after the September 11 attacks . During these seven years , two plots resulted in attacks , compared to the two attacks between May 2009 and November 2010 , which resulted in 14 deaths . This spike post-May 2009 shows that some Americans are susceptible to ideologies that support a violent form of jihad
September 11 attacks
September 11 attacks
Domestic terrorism