The FBI's classification of terrorism into international and domestic is based on geography and not on the goal of the behavior. According to the FBI typology, international terrorism has three subcategories based on the structural organization of the various groups: loosely affiliated extremists, formal terrorist organizations, and state sponsors of terrorism. The first category of international terrorism, loosely affiliated extremists, includes Sunni Islamic extremists, such as Osama bin Laden and those affiliated with his Al-Qaeda organization--individuals from varying nationalities, ethnic groups, tribes, races, and terrorist groups who support extremist Sunni goals. The common element among these diverse individuals is that they are committed to the radical international jihad movement, whose ideology includes promoting violence against the "enemies of Islam" in order to overthrow all governments not ruled by conservative Islamic law. Foreshadowing the American tragedy, in the congressional statement dated May 10, 2001, loosely affiliated extremists were considered the most urgent threat to the US because their goals consisted of carrying out large scale, high profile, high casualty terrorist attacks against US interests and citizens.
The second category of international terrorism, formal terrorist organizations, includes extremist groups such as the Palestinian Hamas, the Irish Republican Army, the Egyptian Al-Gama Al-Islamiyya, and the Lebanese Hizballah. They are characterized as autonomous, generally transnational organizations that have their own infrastructures, personnel, financial arrangements, and training facilities. They have a presence in the US, with members engaged in fund-raising, recruiting, and intelligence gathering. Additionally, they maintain operations and support networks in the US. Prior to September 11, the Hizballah were responsible for the deaths of more Americans than any other terrorist group.
The third category of international terrorism is state sponsors of terrorism, consisting of countries that view terrorism as a tool of foreign policy. At the time of the May 10 congressional statement, the Department of State listed seven countries as state sponsors of terrorism: Iran, Iraq, Sudan, Libya, Syria, Cuba, and North Korea. Iran represented the greatest threat to the US because it supports financially and logistically anti-Western acts of terrorism by others.