Pauling began his career as an instructor and researcher at Cal Tech the same year. For the next twenty years he held a number of important positions in research and academic areas, all the while conducting myriad experiments that would have critical applications in both the hard sciences and medicine. During World War II he worked closely with the federal government. Among many other things, he developed several new explosives and did work to improve medical treatments in combat hospitals.
For all his work and repute in science and medicine, Pauling's social activism earned him the most notoriety. Beginning in the late 1940s, he began to speak out against the construction and testing of atomic weapons. During the McCarthy era, Pauling bravely stood against government-imposed loyalty oaths. His outspokenness resulted in accusations that he was a communist, and for several years the U.S. State Department refused to grant him a passport. In 1954 he won the Nobel Prize for Chemistry, and the State Department changed its position. Beginning in the late 1950s, Pauling was at the fore-front of a movement to ban atmospheric testing of nuclear weapons, which earned him the Nobel Peace Prize in 1962. Indeed, the Partial Test Ban Treaty (PTBT) of 1963 was a direct result of his efforts. Thereafter, he led efforts to curb the production and proliferation of nuclear weapons. He was also an outspoken critic of the Vietnam War, and he openly opposed the 1991 Persian Gulf War, arguing that economic sanctions against Iraq had not been given a chance. In 1991 he wrote "An Appeal for Peace in Croatia," an entreaty to stop the bloodshed in the former Yugoslavia. Pauling died on 19 August 1994 in Big Sur, California.
Paul G. Pierpaoli Jr.
Serafini, Anthiny. Linus Pauling: A Man and His Science. New York: Paragon House, 1991.