the Department of Defense had in fact conducted experiments to influence and control human behavior through the use of psychoactive drugs such as LSD and mescaline and other chemical, biological, and psychological means. Experiments were often conducted without the subjects' knowledge or consent. MK-ULTRA was started on the order of CIA director Allen Dulles, largely in response to alleged Soviet, Chinese, and North Korean use of mind-control techniques on U.S. prisoners of war in Korea. The goal of the experiments was to study mind-control in order to develop methods of interrogation and behavior modification and manipulation, as well as to develop a possible truth drug. Outcome MK-ULTRA research ultimately proved useless to the CIA and they have abandoned the program. Because most MK-ULTRA records were deliberately destroyed in 1973 by order of then CIA director Richard Helms, it is difficult if not impossible to have a complete understanding of the more than 150 individually funded research sub-projects sponsored by MK-ULTRA and related CIA programs. Following the recommendations of the Church Committee, President Gerald Ford in 1976 issued the first Executive Order on Intelligence Activities which, among other things, prohibited "experimentation with drugs on human subjects, except with the informed consent, in writing and witnessed by a disinterested party, of each such human subject" and in accordance with the guidelines issued by the National Commission. Subsequent orders by Presidents Carter and Reagan expanded the directive to apply to any human experimentation. Assassination and targeted killing Targeted killing At least since World War II, a distinction has been drawn between assassination of civilian leaders, and targeted killings of leaders of fighting organizations, including the British-Czech Operation Anthropoid (the killing of SS officer Reinhard Heydrich, acting Reichsprotektor of the Protectorate of Bohemia and Moravia), a failed British attempt to kill Field Marshal Erwin Rommel, and Operation Vengeance, the shooting down of Isoroku Yamamoto by the US Air Force. The CIA has admitted to involvement in assassination attempts against foreign leaders. Recently, there have been targeted killings of alleged terrorists, typically with missiles fired from unmanned aerial vehicles (UAVs) or drones. The Pakistani government, which may "have picked some targets of drone attacks" has criticized the US for drones flying over its territory as an infringement of Pakistani sovereignty. Increased criticism of the CIA drone program has come mostly during the later stages of the war in Afghanistan. One of the main criticisms of