"This report examines international terrorist actions, threats, U.S. policies and responses. It reviews the nation's use of tools at its disposal to combat terrorism, from diplomacy, international cooperation, and constructive engagement to physical security enhancement, economic sanctions, covert action, and military force. A modern trend in terrorism appears to be toward loosely organized, self-financed, international networks of terrorists. Increasingly, radical Islamist groups, or groups using religion as a pretext, pose a serious threat to U.S. interests and to friendly regimes. Of concern as well is the growing political participation of extremist Islamist parties in foreign nations. Also noteworthy is the apparent growth of cross-national links among different terrorist organizations, which may involve combinations of military training, funding, technology transfer, or political advice. Looming over the entire issue of international terrorism is the specter of proliferation of weapons of mass destruction (WMD). Iran, seen as the most active state sponsor of terrorism, has been secretly conducting- and now openly seeks- uranium enrichment, and North Korea has both admitted to having a clandestine program for uranium enrichment and claimed to have nuclear weapons. Indications have also surfaced that Al Qaeda has attempted to acquire chemical, biological, radiological, and nuclear weapons."
CRS Report for Congress, RL33600
U.S. Department of State: http://fpc.state.gov/