Faust: “Well then, who are you?”
Mephistopheles: “A part of that Power which always wills evil and always produces good.”
Of all the species that have ever inhabited our planet, 99% have gone extinct. Nature can be pitiless towards its own creations. Our very existence can be wiped out in the blink of an eye. Throughout history humankind has constantly faced existential crises such as pandemics, plagues, famines, natural disasters, depletion of our natural resources, and climate change. So far, we've survived because most of these catastrophic scenarios were finally solved by our human inventiveness - our technologies. But as we become more technologically adept, we discover that some of the very technologies used to solve our problems have become our problems. But this is history repeating itself, we've been here before.
In 1898, Sir William Crookes addressed the British Association for the Advancement of Science and predicted millions would starve by 1931 because agricultural soils were being depleted of nitrogen. Nitrogen is essential for healthy plant growth. It is a key component of chlorophyll—the green pigment that enables photosynthesis—as well as amino acids and proteins that drive plant development. Scientists believed Earth's population would be limited to around 1.5 billion people as it would be impossible for agriculture to feed anything beyond that.
In the early 1800s huge deposits of sodium nitrate called caliche, or "Chilean saltpeter," were discovered in the Atacama Desert. At the time, caliche was in extreme demand as a fertilizer to replenish agricultural nutrients such as nitrogen.
Outside of the Antarctic, the Atacama Desert is the driest place on Earth. It's a 1,000-mile strip in northern Chile situated between the Andes Mountains and the Pacific Ocean. Vast portions of the desert haven't seen rain for decades. Due to its high altitude and clear atmosphere, the Atacama hosts some of the largest and most powerful telescopes in the world and because of its extreme aridity and rugged landscape, NASA has used it to simulate conditions on Mars.
Caliche was also a valuable resource for gunpowder production throughout the 19th century. Rich in nitrogen compounds, it could be readily refined into potassium nitrate (KNO₃), the essential oxidizing agent that enables gunpowder to burn rapidly creating a sudden burst of hot gas to fire a projectile.
For those living in the 19th century, this unlikely substance supplied critical nutrients for both agriculture and warfare—no wonder it became known as “white gold.”
Although nitrogen makes up about 78 percent of Earth’s atmosphere, plants cannot extract it in its gaseous form and rely upon nitrogen trapped in the soil that, when mixed with water, can be absorbed by their roots. When crops are harvested, or during heavy rainfalls, this soil-bound nitrogen is removed from the soil. Without sufficient nitrogen, yields decline sharply, and soils can become depleted, limiting their ability to support healthy plant growth. To maintain productivity, farmers had to deforest large areas to gain virgin soils, rotate crops, replenish this essential nutrient with organic material such as compost and manure or fertilize using caliche.
19th century scientists knew that large amounts of nitrogen were in our air, but it was unusable. Nitrogen molecules are held together very tightly because they form a triple bond which takes an enormous amount of energy to separate. In nature this can happen during a thunderstorm where lightning strikes in the atmosphere force nitrogen to break its bond then combine with the oxygen in the rainwater and fall as natural fertilizer.
Thunderstorms, crop rotation, replenishing soil with organic materials, and even the addition of caliche didn’t provide nearly enough nitrogen to keep up with the growing demand of a growing world population. Unless there was a way to solve the nitrogen issue, if the world's population continued to expand, millions, particularly in Asia and Africa, would experience devastating famines.
Bread From the Air
In 1909, Fritz Haber discovered a way to extract nitrogen from air and convert it into ammonia fertilizer, a breakthrough that today maintains billions of lives. Few people in history have done more to sustain human life than Fritz Haber. Fewer still have done more to industrialize death.
Fritz Haber was born in Breslau, Prussia (now Wrocław, Poland) in 1868 to non-practicing Jewish parents. Fritz was born into a new, albeit brief, age of religious tolerance in Germany. Following Bismarck's German unification in 1871, for the first time in their history Jews experienced full legal emancipation and political equality throughout the new German Empire as previous restrictions on residency, profession, and marriage were temporarily removed. Growing up, he felt a deep allegiance to the new Second Reich, rather than identifying as a Jew, a religion he never practiced, he considered himself German. In 1892 at the age of 23, Haber was baptized in the Lutheran Church, not for religious purposes, but simply to help assimilate into the new Germany—he stated later, that, “…he had removed the last barrier which had separated him from the Germans.” There would be no question of his allegiance moving forward, he wrote to a friend, "We felt a hundred percent German… and no longer felt any ties to the Jewish religion."
This newly united Germany was quickly evolving from a patchwork of politically fragmented competing states to a dominant cultural, military, industrial, and scientific leader within Europe, inspiring a deep feeling of pride and nationalism in young people like Fritz Haber.
Haber, who possessed an interest in chemistry was allowed to attend university where he met his future wife, Clara Immerwahr, also of Jewish descent. Brilliant in her own right, she was among the first women in Germany to earn a PhD in chemistry.
Fritz Haber became the first chemist to unlock nitrogen's triple bond by combining it with hydrogen gas forming ammonia. By heating nitrogen and hydrogen to nearly 1000°F and subjecting them to extreme pressures approaching 3,000 psi, Haber was able to synthesize ammonia (NH₃) from nitrogen (N₂) and hydrogen (H₂).
When added to soil, ammonia acts as a fertilizer. Some of it dissolves in water to form ammonium (NH₄⁺), while soil bacteria convert ammonia into nitrates (NO₃⁻). Plant roots can absorb both of these forms of nitrogen, supporting vigorous growth and higher yields.
Badische Anilin- & Soda-Fabrik (BASF) held the rights to Haber’s experimental work, which was industrialized on a massive scale by the engineer Carl Bosch. When BASF opened their first processing plant in 1913, the Haber-Bosch process would quickly end the world’s reliance on caliche, enriching centuries old, depleted farmlands to become productive once again. As a result, Fritz Haber gained considerable wealth and was soon one of the world’s most famous scientists.
Haber now found himself within an exclusive cadre of German scientists, such as Albert Einstein, who developed general and special theories of relativity and Max Planck, whose quantum theory was about to change our understanding of physics.
In 1911 Haber was appointed by the Kaiser as the founding director of Kaiser Wilhelm Institute for Physical Chemistry and Electrochemistry in Berlin-Dahlem. Haber spent countless hours working at the institute as well as committing most of his free time to the numerous formal and informal scientific committees and meetings. During the 1920s one of the discoveries made by the Haber's institute was a pesticide named Zyklon A.
His wife Clara, feeling like she had sacrificed her own career wrote to a friend, "What Fritz has achieved in these 8 years, I have lost—and even more. And what’s left fills me with the deepest dissatisfaction….". Instead of pursuing science, Clara was left raising their newborn son, Hermann. She continued in her letter, “Fritz is so scattered, if I didn’t bring him to his son every once in a while, he wouldn’t even know that he was a father.”
Gunpowder From the Air
By 1914, Kaiser Wilhelm II’s abrasive personality, aggressive foreign policy, and determination to secure Germany’s ‘place in the sun’ had helped push Europe toward war. While having just six months' stockpile of caliche-based nitrates for their explosives, Germany had planned for a quick war. But wars seldom go as planned and soon both sides were engaged in a stalemate on the Western Front. Now Germany had to deal with the British Navy’s blockade cutting off all trade heading to Germany, including the critical caliche supplies from the Atacama Desert.
As both sides became bogged down in trench warfare, they were using an incredible amount of gunpowder for the constant bombardment of artillery shells.
Haber was convinced his process could also synthesize nitrates to replace the saltpeter refined from imported caliche. BASF's Carl Bosch quickly transformed ammonia fertilizer plants into industrial nitrate factories. By 1915—less than a year into the war—they were producing 150 tons of nitrate each day. BASF scaled up production at an astonishing rate and by the end of the war, German factories were producing hundreds of tons per day. Historians believe the Haber-Bosch process produced such enormous amounts of nitrates, extending the war by almost three years. Predictably, as the German war machine devoured more and more nitrates for ammunition, farmers were left with less nitrogen for fertilizer. This situation, coupled with the blockade, led to mass food shortages, and even starvation especially through the winter of 1916.
Haber felt that his country had been wronged and added his signature to the "Manifesto of Ninety-Three," a document addressed "To Civilization" claiming Germany was not responsible for starting the war. Instead, it argued that Germany was the victim, not the aggressor. The document ended with a defense of German militarism, stating, "Without German militarism, German culture would long since have been extirpated from the face of the earth…. The German army and the German people are one. This awareness now unites 70 million Germans, irrespective of education, class, or political party…." Besides Haber's signature, it included no less than 13 current or future Nobel laureates. The German science community was now part of its war machine. Haber's friend, Albert Einstein, a pacifist, refused to sign.
Terror From the Air
The international science community was divided on the role of the scientist and how their research was being used in the midst of a world war. Haber, who had embraced German nationalism since his youth had a very clear idea where he stood, "The scientist belongs in wartime, like everyone, to their fatherland. In peacetime he belongs to humanity."
Haber volunteered his Kaiser Wilhelm Institute for military research and, by 1916, it was placed under German military control. Within a year its budget had increased roughly fifty-fold over peacetime levels.
At its wartime peak, Haber was responsible for roughly 2,000 people and his institute focused its efforts on chemical weapons research. Years later his son Ludwig, who became an historian, said of his father, “In Haber, the OHL [German High Command] found a brilliant mind and an extremely energetic organizer, determined, and possibly unscrupulous.”
At 5:00 pm on April 22, 1915, under Fritz Haber's personal direction, German soldiers opened the valves on almost 6,000 high pressure steel tanks unleashing 168 tons of chlorine gas toward the trenches of French and British soldiers guarding their lines near Ypres, Belgium. At first, the Allied soldiers gazed in puzzlement at the mountain of greenish fog almost 50 feet high and four miles wide heading toward them. Once the wind carried it to their trenches they began to cough and choke violently, grabbing at their eyes as they went blind. None of the soldiers had protection from the gas, which opened a five-mile-wide breach in the Allied lines, but the Germans couldn’t take advantage, due to their own incredulity of what they just witnessed. They also couldn't advance as the gas still covered the field. It is estimated that 1,100 Allied soldiers died from this initial gas attack.
After this first successful trial of chlorine gas, Kaiser Wilhelm II promoted Haber from a sergeant of the reserves to a full captain in the German Army. A few weeks later, the delighted Haber returned home to host a celebration at his residence. His guests may have been thrilled at the news coming from the Ypres salient, but his wife Clara was outraged, considering gas warfare to be a “perversion of science” and "a sign of barbarity, corrupting the very discipline which ought to bring new insights into life”.
Soon after the party ended, Clara grabbed Haber's service revolver, walked out of the house and shot herself in the chest. Hearing the gunshot from his bedroom, their son Hermann, age 12, ran out to the courtyard garden where his mother died in his arms. The next morning Captain Haber left for the Eastern Front for more testing, this time on Russian soldiers.
As his research continued, Haber moved his poison gas attacks to artillery shells which could be more accurately aimed and were not dependent on wind direction and speed. He also tested phosgene gas, which is significantly more lethal. Finally he used mustard gas, which was heavier than air and could penetrate deep into Allied trenches and shelters sticking to uniforms, equipment, and even soil, causing chemical burns on contact. At a meeting in 1918 with his colleagues, Haber called the mustard gas attacks a “fabulous success.”
In reality, Haber's appraisal of chemical warfare was exaggerated. The Allied armies quickly developed gas masks and answered by developing their own chemical warfare capabilities. By the war's end, it’s estimated that 91,000 deaths occurred due to poison gas with the majority, about 56,000, occurring on the Eastern Front—Russian soldiers who were woefully under-equipped with protective equipment and medical supplies. Although this is less than one percent of all the military deaths in World War I, poison gas held a particular psychological terror for soldiers. An invisible, silent cloud of gas could engulf them without warning causing traumatic suffering, death, or lifelong injuries.
As a direct result of the terrifying experiences front line soldiers endured during World War I, the Geneva Protocol of 1925 strictly forbade the use of poison gas and twenty years later, even Adolf Hitler who was hospitalized in World War I from a British mustard gas attack, refused to use it, even as his Third Reich crumbled.
Into Thin Air
After Germany's capitulation, the Treaty of Versailles imposed harsh conditions including huge reparation payments to the Allied powers. Haber was outraged, as almost all Germans were, and felt the treaty was humiliating and unfair. To help his country survive its fiscal crisis he once again turned to chemistry. Just as he was able to pull nitrogen from thin air, he felt he could separate dissolved gold from seawater. This isn’t as absurd as it may first appear, Earth's oceans contain an estimated 20 million tons of dissolved gold, more than 100 times all the gold ever mined on land. But this time, of course, Haber was unsuccessful.
In a controversial move, he was awarded the Nobel Prize soon after the war ended. Most people, especially in England, Belgium, and France who had witnessed the effects of poison gas were outraged to see the "father of chemical warfare"—a man many considered a war criminal—conferred such a distinction. But the Nobel committee recognized the significance of his ammonia synthesis process on agriculture and felt it represented the "benefit to humankind" as specified in Alfred Nobel's will.
Through the 1920s the unrest in Germany caused by the injustices of the Versailles Treaty, economic collapse, and civil and political unrest was more than the nascent Weimar Republic could stand. By 1933 Adolf Hitler had become chancellor and moved Germany from a nationalism based on political borders to ethnic nationalism (Ein Volk). Jews, whether converted or not, became disenfranchised. As the Nazi antisemitism grew ever stronger and more violent, Haber followed his colleague Einstein by emigrating out of Germany while he still had the chance.
Rudolf Stern, a former coworker at the Kaiser Wilhelm Institute said of his friend Haber: “…his person was destined to epitomize the great tragedy of an outstanding German Jew who had unsparingly devoted all his mind, his energy and his scientific genius to the German people, only to find himself at the end of his life repudiated and vilified by just this people."
Fritz Haber died alone in a hotel room in Basel, Switzerland in 1934 at the age of 65. The family legacy involving chemical warfare cast a long shadow. His son Hermann, who had held his dying mother in his arms, emigrated to the United States in 1935 with his three daughters and committed suicide in 1946. Hermann's oldest daughter, (Fritz's granddaughter) Claire, herself a chemist, committed suicide in 1949. Fritz's second son, Ludwig, escaped this deadly shadow and decided against a career in chemistry, instead, becoming an historian and eventually publishing a book about the history of poison gas in World War I. In the 1940s the Nazis modified the pesticide, Zyklon A, invented under Haber's direction at his institute into Zyklon B used in the gas chambers of Auschwitz. Numerous Haber family members were gassed including several of Haber's nieces, grandnephews along with numerous friends and professional colleagues.
All generations prior to Fritz Haber lived in constant fear and danger of famine and starvation. Some scientists believe that 3-4 billion people, almost half of Earth's population today, would not survive if it were not for the Haber-Bosch process. Today, food of every kind is so plentiful it is estimated over a billion people, one out of every eight, are suffering from obesity.
Worldwide, almost 174 million tons of ammonia are produced each year and eighty percent of this is used for agricultural fertilizer. We get forty to sixty percent of our protein from animals fed with grain fertilized by Haber's synthesized nitrogen. Some scientists estimate that up to eighty percent of the nitrogen found in our tissues can be traced to the Haber-Bosch process.
When Fritz Haber died, Albert Einstein eulogized him with the words: "Haber's life was the tragedy of the German Jew—the tragedy of unrequited love."
Yet Haber's legacy extends beyond the tragic fate of the assimilated German Jew, there's a deeper meaning to the life of Fritz Haber.
In 19th century Germany, where science and industry had blossomed, technological advancements appeared to be an inevitable step toward progress. Haber wasn't concerned where this new technology led. Defending the use of his latest weapon of poison gas, he stated: “The disapproval that the knight felt for the man with a gun is repeated by the soldier who shoots steel bullets, when confronted by a man who appears with chemical weapons.”
Haber believed in the relentless progress of technology and was unconcerned where this might lead. The Haber-Bosch process has saved billions of lives from starvation and hunger, but it has also led to the overproduction and eventual runoff of ammonium nitrates used in fertilizers creating vast algae blooms and dead zones depriving lakes, rivers and coastal areas of oxygen. The consequences of the Haber-Bosch process has been one of the largest human impacts on our planetary cycle.
How does this differ from our own views of technology today such as artificial intelligence, autonomous weapons systems, genetic engineering, cybersecurity and surveillance? Are we similar to Haber, having faith only in science, simply trusting it will provide positive outcomes for society? In the past, with our technology we have been able to outsmart a relentless and apathetic Nature that continually challenged our existence, but in the future we may have a new adversary—our own technologies. We may have to outsmart ourselves to survive.
The Kaiser Wilhelm Institute was renamed in 1953 in his honor and there is a crater on the far side of the Moon named after him. In 1957 his image appeared on a West German postage stamp. But for the man whose brilliance enabled an extra three billion people to not only survive but to live comfortably, there are no statues to Fritz Haber, no holidays in his honor, almost nothing for us to remember him by. Fritz Haber's life is a lesson for every scientist, engineer, and technician. We all seek a legacy of technological progress and improvement, but an unbridled allegiance fused with blind ambition, an unwavering faith in our own creations, and an unwillingness to confront moral questions can lead to the tragedy of Fritz Haber. Realizing such a lesson would be a more genuine and useful remembrance of his brilliant, yet tragic life. Fritz Haber should be viewed as a warning.