“I’m worried about anyone who could end civilization, and not just about certain nations,” reflected Martin Hellman M.S.’67 Ph.D.’69, professor emeritus of electrical engineering, on nuclear weapons.

To the broader world, Hellman may be best known for his invention of public-key cryptography, which underpins modern telecommunications security. For current students, however, he is perhaps most closely associated with his efforts towards spreading awareness on campus about nuclear threats.

For the past few years, Hellman has gone from dorm to dorm putting up posters to advertise his website, NuclearRisk.org, which provides information about how students can get involved in reducing the threat of nuclear weapons through grass-roots advocacy.

Matthew Colford ’14, who lived in Florence Moore Hall as a freshman, was encouraged by Hellman to promote nuclear awareness among his dormmates.

“He was great to meet,” Colford said of Hellman. “He was very passionate, and as a freshman, meeting someone like him was a fascinating experience—I was in awe.”

Even with such a diverse range of interests, Hellman emphasized the continuity in his experiences, framing his invention of public-key cryptography—in collaboration with Whitfield Diffie and Ralph Merkle Ph.D.’79—in the context of his sustained interest in engineering, which started at an early age.

“I liked knowing how everything worked,” he said. “I took my bike apart down to the ball bearings as a child, and once I found out about engineering, it made sense [to study it].”

After finishing high school in his native New York City, Hellman decided to pursue engineering on a scholarship at New York University. After finishing his degree in 1966, he came to Stanford to continue his studies, a decision he said was easy to make.

“It wasn’t so much Stanford, but rather, it was California in the 1960s,” Hellman said. “It had some kind of an aura around it, which certainly has been borne out—it is a land of opportunity in ways that the place I grew up in was not.”

After receiving his master’s and doctorate degrees on the Farm, Hellman returned to the East Coast to work at IBM and later taught engineering at Massachusetts Institute of Technology. In 1971 Hellman returned to Stanford as a professor, a position he held until he became professor emeritus in 1996 after 25 years on the job.

Hellman commented that his interest in cryptography came out of interactions he had while working at IBM in the late 1960s.

“I went to IBM Research immediately after my Ph.D. because my thesis broke so quickly that I didn’t have time to look for a teaching job,” he said.  “IBM was in the forefront, really, of commercial encryption.”

Hellman said he had been working one night on developing an algorithm involving a string of data to be transmitted from a sender and recipient with two different keys, an idea that stemmed from an earlier conversation with coworkers. After checking his work on an HP-40 calculator, the math seemed to work out and his invention snowballed from there.

“IBM was spending money and resources on this [idea], and so I foresaw a need for this as computers and information communication became more married,” he said.

After gaining wide recognition in the field of cryptography, Hellman developed his interest in nuclear nonproliferation, a field introduced to him by his wife.

“Around 1980, she got interested in these ideas and then brought me along,” he said. “We both got convinced that a single caring individual could make a difference in this world of ours. One of the partners at my wife’s firm invited me to come to a meeting of a group called Creative Initiative, which was pushing for this idea.”

As the two became more and more invested in their pet project and as the events of the late 20th century unfolded, Hellman came to view nuclear weapons as an increasingly dangerous threat that warranted heightened attention in the academic community.

“As we researched, we concluded that we could not separate the nuclear threat from the threat of war itself,” he said. “We concluded we would never get rid of nuclear weapons or the threat of nuclear weapons, and the most likely trigger for a nuclear war would be some global hotspot.”

In an effort to promote awareness among students on campus, Hellman teaches STS 152: Nuclear Weapons, Risk and Hope. The course deals with the concept of combating nuclear threats.

Hellman clarified that his research has not only focused on nuclear nonproliferation, but also on the control and elimination of the weapons already available.

“One thing I am doing there is to study how risky it is to rely on nuclear weapons for our security,” he said. “I do feel that nuclear weapons have lengthened the time between wars, but I don’t think that they have eliminated the threat entirely.”

Even as his career tilts away from his background in electrical engineering, Hellman has continued to gain plaudits for his work in cryptography, including induction into the Silicon Valley Hall of Fame earlier this year.

Hellman posited that there is a place for both his passions—cryptography and awareness of nuclear threats—in Silicon Valley.

“Silicon Valley epitomizes new ideas, interesting ideas,” he said. “One of the things that was particularly meaningful about [my award] is the role that Silicon Valley plays rewarding what I call foolishness—it rewards people who do crazy things.”