"Political Violence Against Americans is a report to the American people that focuses on major incidents of anti-U.S. violence and terrorism, with apparent political motivations, that occurred worldwide during 2010. The U.S. Department of State closely monitors and maintains information on threats to Americans overseas -- from terrorism and organized violence, to street crimes and health hazards -- and makes this information freely available. It is the policy of the U.S. Government that no double standard shall exist regarding the dissemination of threat information that affects U.S. citizens. Government employees may not benefit unfairly by access to, or possession of privileged information that applies equally to all Americans. In view of the enormous number of hostile incidents that occur universally in the course of a year, the particular events cited in Political Violence Against Americans were selected based upon certain specific criteria in addition to their political nature, including one or more of the following: the presence of casualties, substantial property damage, or the use of unusual tactics and weapons, together with a perception of the targets as intentionally those of the United States, or representative of U.S. interests. The incidents included here were reported to Department of State Diplomatic Security personnel posted at U.S. missions worldwide, and comprise the best information (sometimes incomplete) that is available. Some incidents are never reported to U.S. officials, of course. A few unique incidents have been omitted due to their sensitive nature, as have the names of American citizens for privacy purposes."
U.S. Department of State: http://www.state.gov/