How Albert Einstein's Politics Left Him Off The Manhattan Project

Some remember Albert Einstein by his Bernie Sanders hair and quirky personality. Others falsely credit him with inventing nuclear weapons, according to the American Museum of Natural History. But most know Einstein for his legendary contributions to science, with his discovery of the theory of general relativity and the legendary E=mc² equation that among other discoveries won him the Nobel Prize in Physics in 1921 (via EarthSky, Atomic Heritage).

As a teenager, Einstein abandoned his German citizenship and eventually got a passport from neutral Switzerland. Later, he moved to the U.S. and became a citizen in 1940, just as Adolf Hitler was rising to power in Germany (via Atomic Heritage). But despite his citizenship and contributions to science, Einstein was ostracized by the U.S. government, which kept a 1,427-page FBI file on him and ultimately didn't find him trustworthy enough to work on the Manhattan Project during the war.

'An extreme radical'

Before World War II started, Einstein was friends with Fritz Haber, who became known as the "father of chemical warfare" for inventing a chlorine gas commonly used to kill (per National Geographic). Einstein also had an affair with a woman, Margarita Konenkova, who was thought by some to be a Russian spy (per National Geographic).

But it wasn't these connections that made the U.S. government suspicious of him. Actually, Einstein was a civil rights activist, testifying on behalf of W.E.B. Du Bois in a 1951 trial that ultimately dismissed his case (via National Geographic). It was Einstein's activism that made the FBI start keeping tabs on him as a potential communist and "extreme radical," according to National Geographic.

As the war progressed, Einstein discovered through his lasting German connections that the Nazis were in the process of one of the most controversial discoveries in human history with the advent of the atom bomb, per the AMNH. In an attempt to alert authorities, Einstein wrote a letter to President Franklin Roosevelt in 1939 explaining the situation (via AMNH).

A letter to the president

Nearly one year later, when the Nazis began the bombing of Britain, Albert Einstein was deemed too shady to work on the Manhattan Project, which would ultimately produce the country's first nuclear weapons (per AMNH). Perhaps the U.S. government would second-guess the dismissal of one of the greatest scientists in recent times if they knew what we knew today about Einstein's lasting contributions to science. But for Einstein's part, he didn't seem to be bothered by the rejection. According to The New York Times, Einstein later expressed regret in sending that 1939 letter. Ultimately, the Germans did not develop an atomic bomb, and without the letter, it's possible the U.S. wouldn't have either.

After the tragic bombing of Hiroshima, Einstein became an anti-nuclear activist, saying the world was drifting "toward unparalleled catastrophe" with the potential violence nuclear weapons held, per The New York Times. Still, in a world of what ifs, hundreds of other scientific developments would perhaps not have been fulfilled had it not been for Einstein's letter, which spurred an enormous investment in scientific research (via The New York Times).