Perversion of the ideals of Science

Haber greeted World War I with enthusiasm, joining 92 other German intellectuals in signing the Manifesto of the Ninety-Three (proclamation endorsed by 93 prominent German scientists, scholars and artists, declaring their unequivocal support of German military actions in the early period of World War I) in October 1914. Haber played a major role in the development of the non-ballistic use of chemical warfare in World War I, in spite of the proscription of their use in shells. He was promoted to the rank of captain and made head of the Chemistry Section in the Ministry of War soon after the war began. In addition to leading the teams developing chlorine gas and other deadly gases for use in trench warfare, Haber was on hand personally when it was first released by the German military at the Second Battle of Ypres (22 April to 25 May 1915) in Belgium.

Regarding war and peace, Haber once said, "During peace time a scientist belongs to the World, but during war time he belongs to his country." This was an example of the ethical dilemmas facing chemists at that time. In his studies of the effects of poison gas, Haber noted that exposure to a low concentration of a poisonous gas for a long time often had the same effect (death) as exposure to a high concentration for a short time. He formulated a simple mathematical relationship between the gas concentration and the necessary exposure time. This relationship became known as Haber's rule. Haber defended gas warfare against accusations that it was inhumane, saying that death was death, by whatever means it was inflicted.

Suicide of his Wife, Clara Immerwahr

Clara Immerwahr was the first woman to earn a PhD (in chemistry) at the University of Breslau. Clara was a women's rights activis s well as a Pacifist(opposition to war, militarism, or violence). Intelligent and a perfectionist, she became increasingly depressed after her marriage and the loss of her career.

Confiding in a friend, Immerwahr expressed her deep dissatisfaction with this subservient role:

It has always been my attitude that a life has only been worth living if one has made full use of all one's abilities and tried to live out every kind of experience human life has to offer. It was under that impulse, among other things, that I decided to get married at that time... The life I got from it was very brief...and the main reasons for that was Fritz's oppressive way of putting himself first in our home and marriage, so that a less ruthlessly self-assertive personality was simply destroyed.

During World War I, Fritz Haber became a staunch supporter of the German military effort and played an important role in the development of chemical weapons (particularly poison gases). His efforts would culminate in his supervision of the first successful deployment of a weapon of mass destruction in military history, in Flanders, Belgium on 22 April 1915. Immerwahr spoke out against her husband's research as a "perversion of the ideals of science” and “a sign of barbarity, corrupting the very discipline which ought to bring new insights into life."

Shortly after Haber's return from Belgium, Immerwahr shot herself in the chest using Haber's military pistol. On 2 May 1915, she died in her son's arms. The morning after her death, Haber left for the first gas attack against the Russians on the Eastern Front.

Her suicide may have been in part a response to Haber's having personally overseen the first successful use of chlorine gas during the Second Battle of Ypres, resulting in over 67,000 casualties. Her reasons for suicide have been the subject of speculation.