John Harold Marcer was 15 years old when Adolf Hitler signs an order to begin the systematic euthanasia of mentally ill and disabled people. Adolf Hitler was a German politician, demagogue, and Pan-German revolutionary, who was the leader of the Nazi Party, Chancellor of Germany from 1933 to 1945 and Führer ("Leader") of Nazi Germany from 1934 to 1945. As dictator, Hitler initiated World War II in Europe with the invasion of Poland in September 1939, and was central to the Holocaust.
John Harold Marcer was 16 years old when The Holocaust: The first prisoners arrive at a new concentration camp at Auschwitz. The Holocaust, also referred to as the Shoah, was a genocide during World War II in which Nazi Germany, aided by its collaborators, systematically murdered some six million European Jews, around two-thirds of the Jewish population of Europe, between 1941 and 1945. Jews were targeted for extermination as part of a larger event involving the persecution and murder of other groups, including in particular the Roma and "incurably sick", as well as ethnic Poles and other Slavs, Soviet citizens, Soviet prisoners of war, political opponents, gay men and Jehovah's Witnesses, resulting in up to 17 million deaths overall.
John Harold Marcer was 33 years old when Space Race: Launch of Sputnik 1, the first artificial satellite to orbit the Earth. The Space Race refers to the 20th-century competition between two Cold War rivals, the Soviet Union (USSR) and the United States (US), for dominance in spaceflight capability. It had its origins in the missile-based nuclear arms race between the two nations that occurred following World War II, aided by captured German missile technology and personnel from the Aggregat program. The technological superiority required for such dominance was seen as necessary for national security, and symbolic of ideological superiority. The Space Race spawned pioneering efforts to launch artificial satellites, uncrewed space probes of the Moon, Venus, and Mars, and human spaceflight in low Earth orbit and to the Moon.
John Harold Marcer was 39 years old when John F. Kennedy was assassinated by Lee Harvey Oswald in Dallas, Texas; hours later, Lyndon B. Johnson was sworn in aboard Air Force One as the 36th President of the United States. John Fitzgerald Kennedy, commonly referred to by his initials JFK, was an American politician who served as the 35th President of the United States from January 1961 until his assassination in November 1963. He served at the height of the Cold War, and the majority of his presidency dealt with managing relations with the Soviet Union. As a member of the Democratic Party, Kennedy represented the state of Massachusetts in the United States House of Representatives and the U.S. Senate prior to becoming president.
John Harold Marcer was 49 years old when Vietnam War: The last United States combat soldiers leave South Vietnam. The Vietnam War, also known as the Second Indochina War, and in Vietnam as the Resistance War Against America or simply the American War, was a conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. It was the second of the Indochina Wars and was officially fought between North Vietnam and the government of South Vietnam. The North Vietnamese army was supported by the Soviet Union, China, and other communist allies; the South Vietnamese army was supported by the United States, South Korea, Australia, Thailand and other anti-communist allies. The war is considered a Cold War-era proxy war by some US perspectives. The majority of Americans believe the war was unjustified. The war would last roughly 19 years and would also form the Laotian Civil War as well as the Cambodian Civil War, which also saw all three countries become communist states in 1975.
John Harold Marcer was 62 years old when Space Shuttle program: STS-51-L mission: Space Shuttle Challenger disintegrates after liftoff, killing all seven astronauts on board. The Space Shuttle program was the fourth human spaceflight program carried out by the National Aeronautics and Space Administration (NASA), which accomplished routine transportation for Earth-to-orbit crew and cargo from 1981 to 2011. Its official name, Space Transportation System (STS), was taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development.
John Harold Marcer was 75 years old when Columbine High School massacre: Eric Harris and Dylan Klebold killed 13 people and injured 24 others before committing suicide at Columbine High School in Columbine, Colorado. The Columbine High School massacre was a school shooting that occurred on April 20, 1999, at Columbine High School in Columbine, an unincorporated area of Jefferson County, Colorado, United States, in the Denver metropolitan area. In addition to the shootings, the complex and highly planned attack involved a fire bomb to divert firefighters, propane tanks converted to bombs placed in the cafeteria, 99 explosive devices, and car bombs. The perpetrators, senior students Eric Harris and Dylan Klebold, murdered 12 students and one teacher. They injured 21 additional people, and three more were injured while attempting to escape the school. The pair subsequently committed suicide.