Haber was the professor of Physical and electrochemical chemistry at Karlshruhe Institute of Technology, in early 20th century Germany, when he was seized of the fact that the world cannot produce enough food to feed its ever growing population. He was a Jewish born Christian convert who was ambitious and loyal to the German establishment. The fertilizer used in food production until that time were the saltpeters ( Nitrates) coming from Chile, SA. Surely, that would run out.
While everyone knew that the atmosphere is made up of 78% nitrogen, no one had a way use it to support plant life for which it is crucial. Haber, found a way to convert atmospheric nitrogen into the ammonia compound that could be used in fertilizers, in 1909. It took more than 4 years for it to be synthesized in the large-scale production of fertilizers by Carl Bosch with the use of Hydrogen. The Haber-Bosch method is considered one of the most important innovations of the 20th century, which won both Haber (1918) and Bosch ( 1931) the Nobel price. The same process that helps feed millions also helps destroy as it is used in making ammunition.
Haber became the director of the Kaiser Wilhem Institute in 1911 and enthusiastically ensured and justified the use by Germany of Chlorine gas during World War I. It is often said that World War I was the Chemists’ war for had it not been for innovations like the Haber-Bosch process of Ammonia synthesis, Germany couldn’t have stayed in the war that long. He paid a heavy personal price for his support of the use of chemical weapons in the War, as his wife was extremely distressed by it and committed suicide.
He was rejected over time by the scientific community for his role in chemical warfare. His loyalty to Germany was also challenged as his Jewish heritage came into play under Nazi Germany and he was accused of harboring Jewish scientists, who he was forced to fire, at the Kaiser Wilhem institute. He left Germany in 1933 without a permanent home as he looked for employment in various places. In an ironic turn of events, one of the insecticides that Haber helped develop -Zyklon A, was widely used to kill detainees in Nazi concentration camps during World War II and may have killed many of his relatives. He died in 1934 of a heart attack in Switzerland, a contrite and heartbroken man for the role he played for Germany in World War I. Germany was not the only country to use chemical weapons in World War I and he wasn’t the only scientist aiding that process in a war that displayed large scale use of these weapons.
However, he was a bundle of contradictions – a hero for creating a product that helps feed people while at the same time a villain for supporting the production of weapons and poison gases. He also paid the highest personal price for his choices as he lost friends and family because of his decisions. His conversion to Christianity from Judaism, also came to naught. For these reasons, he remains a controversial figure in the scientific community.