He flew missions in Consolidated B-24 Liberator bombers with the 93rd Bombardment Group in the European theatre of World War II.

[5][6] In 1985, Klinghoffer (then 69, retired, and using a wheelchair) was on a cruise on the Achille Lauro with his wife Marilyn to celebrate their 36th wedding anniversary.

Additionally, Klinghoffer was Jewish and American, and his wheelchair made him both difficult to move around the ship and his absence less likely to cause resistance among the surviving hostages.

One of the hijackers, Youssef Majed al-Molqi, later gave a statement on why he was chosen: "I and Bassm [al-Ashker] agreed that the first hostage to be killed had to be an American.

Molqi ordered Manuel De Souza, a Portuguese waiter, to accompany him and push Klinghoffer outside onto the open deck.

When De Souza was unable to do the task alone, Molqi found Italian hairdresser Ferruccio Alberti and forced the two of them at gunpoint to throw the body and then the wheelchair into the sea.

Palestine Liberation Organization (PLO) Foreign Secretary Farouq Qaddumi said that perhaps the terminally ill Marilyn had killed her husband for insurance money.

After an extradition dispute, Italian authorities arrested and tried the Palestinian terrorists but decided that there was insufficient evidence to associate Abu Abbas with the hijacking.

[13] Five days after the murder, Rabbi Morris Gordon and a group of student activists performed a mock Jewish funeral service for Leon Klinghoffer in front of the Palestine Liberation Organization's Washington, D.C., office to call attention to the group's role in the killing of an American military veteran.

[15] This lawsuit spurred passage of the Antiterrorism Act of 1990, which made it easier for victims of terrorism to sue terrorists and collect civil damages for losses incurred.

The Clinton administration, aware of Abbas' arriving in Gaza, neither asked for his extradition nor requested he be given to Italy who had found him guilty in absentia.

[17] The ship involved in the hijacking, the Achille Lauro, returned to cruise duty until it was caught afire off the coast of Somalia on November 30, 1994.

[18][19] The hijacking was made into a television movie in 1990, Voyage of Terror: The Achille Lauro Affair featuring Burt Lancaster and Eva Marie Saint.

The concept of the opera The Death of Klinghoffer originated with theatre director Peter Sellars,[20] who was a major collaborator, as was choreographer Mark Morris.

[21] A Prix Italia-winning television version of the opera, starring Sanford Sylvan and Christopher Maltman, and directed by Penny Woolcock, was screened by United Kingdom's Channel 4 in 2003.

Klinghoffer (and his supposed travel diary) play a minor role in Philip Roth's 1993 novel Operation Shylock.