State terrorism
While the most common modern usage of the word terrorism refers to civilian-victimising political violence by insurgents or conspirators, several scholars make a broader interpretation of the nature of terrorism that encompasses the concepts of state terrorism and state-sponsored terrorism. Michael Stohl argues, "The use of terror tactics is common in international relations and the state has been and remains a more likely employer of terrorism within the international system than insurgents. Stohl clarifies, however, that "[n]ot all acts of state violence are terrorism. It is important to understand that in terrorism the violence threatened or perpetrated, has purposes broader than simple physical harm to a victim. The audience of the act or threat of violence is more important than the immediate victim."
Islamic terrorism
Al-Qaeda's stated aim is the use of jihad to defend and protect Islam against Zionism, Christianity, Hinduism, the secular West, and Muslim governments such as Saudi Arabia, which it sees as insufficiently Islamic and too closely tied to the United States. Formed by Osama bin Laden and Muhammad Atef in the aftermath of the Soviet–Afghan War in the late 1980s, al-Qaeda called for the use of violence against civilians and military of the United States and any countries that are allied with it.