Assassins (literally “eaters of hashish”) were an order of Muslim fanatics who specialized in killing Christian crusaders during the Middle Ages. In recent decades, “assassination” has come to refer almost exclusively to the murder of politically prominent persons. For example, whereas Mark David Chapman is the “murderer” of John Lennon, Lee Harvey Oswald was the “assassin” of John F. Kennedy.

The most shocking and controversial assassinations were the trio of killings in the 1960s, taking the lives of John and Robert Kennedy and Martin Luther King, Jr. The November 22, 1963 assassination of President Kennedy became one of those moments locked in Americans’ memories; people who remember the assassination can recall exactly what they were doing and how they felt when they heard the news. All three deaths evoked massive outpourings of public grief. Following Dr King’s death, riots broke out in several US cities because the assassination of the Civil Rights movement’s moral leader seemed to undermine any hope African Americans held for racial justice.

The official media and government response to the assassinations was to reassure the public that the assassins’ bullets could not damage the operation of the nation’s democratic institutions. The reassurance occasionally included positive actions, such as when President Johnson linked John Kennedy’s martyrdom with the passage of the Civil Rights Acts of 1964 and 1965. Typically, many citizens have not been so easily reassured, and their doubts have led them to believe that, had President Kennedy lived, he would not have become deeply involved in the Vietnam War, or that Robert Kennedy would have won the 1968 presidential election and prevented much of the ensuing divisiveness in the nation’s political culture.

In all three assassinations, a prime suspect was quickly identified, convicted in the court of public opinion, and marginalized as a lone fanatic, unconnected with any powerful groups that might have profited from the assassination. Moreover, in all three cases, the assassination investigations were hastily completed, leaving many alternative hypotheses untested. Furthermore, the importance of the FBI in conducting these investigations calls their findings into question because Bureau Director J. Edgar Hoover hated the Kennedys and King. In fact, the House Select Committee on Assassinations repudiated the key finding of the Warren Commission by asserting that Oswald did not act alone in killing President Kennedy, and was most likely carrying out the plans of organized crime leaders.

The controversy over these assassinations persists. Supporters of the official explanations find a platform in the media, whereas critics are given little access and are demeaningly called “conspiracy buffs.” Controversies were fueled by Oliver Stone’s proconspiracy movie JFK (1991), and by the flurry of media stories arising from the King family’s support of James Earl Ray’s request for a trial in the year before his 1998 death.