"The Islamic State (IS, aka the Islamic State of Iraq and the Levant, ISIL/ISIS, or the Arabic acronym 'Daesh') is a transnational Sunni Islamist insurgent and terrorist group that controls large areas of Iraq and Syria, has adherents in several other countries, and disrupts regional and international security with violence and terrorism. A series of terrorist attacks attributed to the group outside of Iraq and Syria during 2015 has demonstrated IS supporters' ability to threaten societies in the Middle East, Africa, Europe, and the United States, including in countries with sophisticated and capable intelligence and security forces. The group has stated its intent to attack inside the United States, and the December 2015 shootings in San Bernardino, California, have been attributed to IS supporters who did not have apparent links to the organization. Debate continues over whether IS elements overseas have the capability to direct, support, and/or carry out further attacks in the United States. Members of Congress and Obama Administration officials have spoken with increasing concern about the group's ability to threaten U.S. interests and partners abroad, its engagement in terrorist attacks outside of its core areas of operation, and its stated intent to attack the United States at home and overseas or to inspire others to do so. IS claims of responsibility in November 2015 for the apparent bombing of a Russian airliner in Egypt, a suicide bombing attack in Beirut, and a multi-pronged assault in central Paris intensified debate about U.S. strategy, policies, and options. The group's statements suggest it seeks to provoke reactions from targeted populations and spur confrontations between various Muslim sects and between Muslims and non-Muslims. […] This report provides background on the Islamic State organization, discussing its goals, operations, and affiliates, as well as analyzing related U.S. legislative and policy debates."
CRS Report for Congress, R43612
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html