John G. Trump

John George Trump (August 21, 1907 – February 21, 1985) was an American electrical engineer and professor at the Massachusetts Institute of Technology (MIT). He pioneered the use of high-voltage generators in cancer treatment and was founding chairman of High Voltage Engineering Corporation, a leading manufacturer of particle accelerators.

Trump received his electrical engineering doctorate as the first student of MIT physicist Robert J. Van de Graaff. He joined MIT's faculty in 1935 and designed compact, high-voltage Van de Graaff generators for use in cancer radiotherapy. Trump later directed MIT's High Voltage Research Laboratory, which developed new radiotherapy techniques, trained radiologists, and treated more than 10,000 patients. Under Trump, the lab explored the generation and use of electrostatic power in medical sterilization, spacecraft propulsion, wastewater disinfection, and direct current power transmission.

Ahead of American entry into World War II, Trump joined the National Defense Research Committee (NDRC), the government's main effort to organize civilian scientists for war. As technical aide to Karl Compton, he helped establish the Radiation Laboratory to develop microwave radar. He served on the lab's steering committee and as an NDRC divisional secretary, managing the NDRC's portfolio of radar contracts. In February 1944, he went to England to direct the Rad Lab's field operation in Europe. There, he organized radar deployments for the D-Day invasion, aided interception of V-1 missiles, and advised American commanders on radar use in combat. He received service commendations from President Truman and King George VI.

In 1946, Trump organized the High Voltage Engineering Corporation (HVEC) with Van de Graaff and Denis Robinson to build compact Van de Graaff accelerators for cancer therapy. They received one of the first three investments of the American Research & Development Corporation, the first modern venture capital firm. As chairman, Trump oversaw the company's growth and debut on the New York Stock Exchange. HVEC became the largest global supplier of research particle accelerators as government funding for nuclear science expanded, and later diversified into industrial products.

Trump retired from the MIT faculty in 1973 and remained active as a trustee of Boston's Museum of Science and board chairman of the Lahey Clinic, a regional hospital. President Reagan awarded Trump the National Medal of Science in 1983 for the "beneficial application of ionizing radiation to medicine, industry and atomic physics." Trump was the paternal uncle of Donald Trump, the 45th and 47th president of the United States.

Early life and education New York years (1907–1931) Born in the Bronx, New York City, on August 21, 1907, John Trump was the youngest of three children born to German immigrants Frederick and Elizabeth Christ Trump. After the Queensboro Bridge opened in 1909, the family moved to Queens, eventually settling in the Woodhaven neighborhood. When Trump was 11, his father died in the 1918 influenza pandemic, leaving his mother to support the family.

Like his siblings, Trump attended Richmond Hill High School, where he was a gifted student. He joined Western Electric's Manhattan engineering office in 1923, two years before it became known as Bell Labs.

Both John Trump and his older brother Fred joined their family's real estate firm. Their mother hoped that Fred would build homes and John design them. With support from his brother, John enrolled at Brooklyn Polytechnic Institute to study architecture. The brothers' work together ended due to differences in business philosophy: Fred preferred to sell units as they were planned; John thought they should only sell once constructed. By the end of his freshman year, John left the family real estate business and switched his concentration from architecture to engineering.

Selected as Brooklyn Poly's valedictorian, Trump graduated from in 1929 with a bachelor's degree in electrical engineering. While teaching electrical engineering at his alma mater, he earned his master's degree in physics from Columbia University in 1931.

MIT doctorate (1931–1933)

In fall 1931, Trump arrived at the Massachusetts Institute of Technology (MIT) to pursue a PhD in electrical engineering. MIT's new president, the physicist Karl Compton, was recruiting scientists to strengthen basic research at the institute. Vannevar Bush, dean of MIT's engineering school, recommended Trump work with one of these recruits: Robert J. Van de Graaff, a 29-year-old physicist developing a new electrostatic generator. Van de Graaff became Trump's advisor and lifelong collaborator.

Van de Graaff sought to build a generator with sufficiently strong electric potential to artificially split the atom. He split his research between open-air models, which required large terminals, and vacuum-insulated designs, which were compact but technically challenging. In 1933, Van de Graaff demonstrated the Round Hill generator, a air-insulated generator that produced dramatic electrical arcs and attracted broad press coverage. But the demonstration also revealed the design's fundamental limitation: high voltages broke down in open air.

To overcome these limits, Trump worked on vacuum techniques. He designed a synchronous alternating-current motor to power a vacuum, which proved highly efficient. Encouraged by this practical innovation, his dissertation also proposed a method to build vacuum-insulated, long-distance transmission lines for high-voltage direct current. In 1932, Van de Graaff filed to patent components in the transmission system. The new Tennessee Valley Authority showed interest in developing these patents for its hydropower projects, and Vannevar Bush offered to license them to the TVA by assigning them to the Research Corporation. Though the transmission project fell through, MIT became the first private university with a policy of research commercialization, and its arrangement was an influential predecessor to university patent licensing.

Trump received his doctorate of electrical engineering in 1933. His thesis, Vacuum Electrostatic Engineering, described these contributions and examined the factors governing voltage-insulation strength in vacuums.

Early career After graduating, Trump remained at MIT as a research associate, then became an assistant professor in 1936. His research focused on improving high-voltage generators and finding new uses for them in industry.

While writing his thesis, Trump had learned about an MIT lecture on medical uses of high-voltage x-rays. At the time, low-voltage radiotherapy techniques could only target superficial tissues and required long exposures that damaged skin. Because Van de Graaff sources produced steady, controllable, power that other high-voltage sources could not, Trump hypothesized that they could produce penetrating, precise x-rays that could target deeper tumors.

In May 1935, Trump showed that striking a gold target with the Van de Graaff electron beam produced abundant x-rays. The Godfrey M. Hyams Trust funded the construction of a 1-MV generator for Harvard's Huntington Memorial Hospital, which entered service in March 1937. The first of several hospital generators Trump would build, it required a room-sized voltage terminal with an internal focusing coil suspended over the patient in the room below. Though just one-third the height of the Round Hill generator, its operators saw it as "magnificent monster." Radiologists reported that it provided "increased depth dosages, greater skin sparing, and greater intensity" than radium exposure, then the prevailing technique. The first patient treated by the Huntington machine survived beyond four years.

Trump's gas-insulated generator would find other commercial applications. With World War II engulfing Europe and Asia, the United States began expanding its military fleet production. With engineers at Boston Navy Yard, Trump discovered that his high-voltage x-ray generator could detect manufacturing defects in ships and aircraft. Robert Van de Graaff carried this work forward through MIT's High Voltage Radiographic Project, supplying generators for Navy efforts to inspect ship hulls and captured enemy munitions.

World War II service Radiation Laboratory administration

During World War II, Trump interrupted his research on x-ray therapy to work on military uses of microwave radar. In June 1940, Vannevar Bush organized the National Defense Research Committee (NDRC) to direct the White House's wartime research strategy. Trump joined the NDRC as technical aide to MIT president Karl Compton, who chaired the committee's radar and detection section (Division D).

Then a government employee, Trump was called upon for his expertise in direct-current electrical equipment, which overlapped Tesla's work. After a three-day investigation in Manhattan, Trump reported in a classified memo to OAPC that the materials had neither military value to the United States nor would "constitute a hazard in unfriendly hands." In the memo, Trump expressed admiration for Tesla's well-known inventions, but assessed that his late-career ideas were "somewhat promotional" and "did not include new sound workable principles or methods." Technical papers describing the weapon were discovered at Yugoslavia's Nikola Tesla Museum in 1984 and did not overturn Trump's assessment.

Service in Europe (1944–1945)

Late in 1943, the NDRC established the British Branch of the Rad Lab (BBRL) at Great Malvern, England, home of the British Telecommunications Research Establishment, to coordinate radar support for the planned invasion of Europe. In February 1944, Trump was chosen to reorganize and expand the overseas laboratory, and was tasked with clarifying its relations with the British service, securing more staff, and determining its program for the coming months. What was expected to be a three- or four-month assignment would last fifteen months, from D-Day planning until the fall of Berlin. On February 26, Trump flew to England with DuBridge, Bowles, and physicist Louis N. Ridenour. He would expand BBRL into a roughly 100-member field operation.

Trump was one of a few civilians read into secret Operation Overlord (D-Day) plans. He served on a joint civilian committee advising SHAEF on the use of radar and countermeasures in the invasion, and worked alongside a separate Advisory Specialist Group (ASG) of radar experts attached to General Carl Spaatz's headquarters. In the months before D-Day, Trump and Ridenour promoted the modification of SCR-584 radar sets for close air support, using ground radar to guide fighter-bombers onto targets through cloud cover. After a successful demonstration for 9th Air Force officers in May 1944, BBRL supervised the modification program. The branch also prepared the first deployment of Microwave Early Warning (MEW) radar, a long-range system for monitoring aircraft formations and directing fighter operations from the ground.

On D-Day, MEW Radar installed by BBRL watched and coordinated landings. On D-Day, the influence of the civilian radar specialists was evident. German coastal radars were jammed and deceived; radar beacons marked the paratroop drop zones behind the beaches; and H2X radar guided the bombing of beachfront fortifications ahead of the assault forces. MEW Radar, activated for the first time on June 6, documented from England the parachute drops and aerial bombings that preceded the troop landings. When Germany began launching V-1 flying bombs against England in the week after the landings, BBRL diverted its long-range radar to detect the rockets offshore. Working alongside gun-laying radar and the proximity fuse, these combined defenses progressively suppressed the V-1 attacks. In August 1944, Trump followed Allied forces onto the continent, arriving in Paris on the final day of its liberation, where he established an Advanced Service Base for forward operations.

The ground-controlled close air support technique that Trump championed in Europe proved to be one of the war's important tactical innovations. It enabled Allied air forces to support ground troops even in poor weather, as when radar-guided fighters broke through overcast to repel a German tank attack on Patton's forces in October 1944. In November 1944, he was formally appointed to the Advisory Specialist Group, joining Ridenour as a civilian advisor to General Spaatz on navigational radar, precision bombing, and countermeasures. Trump's dual role in the BBRL and the specialist group integrated two organizations that had previously operated in parallel.

Science historian Henry Guerlac described Trump as "one of the most respected and influential scientific figures in the entire theater," crediting his effectiveness to "personal ability, reliable judgment, quiet charm, and great patience." General Spaatz echoed this assessment in a letter to General Arnold, calling BBRL "one of the most important factors contributing to our success" and requesting the organization be augmented rather than reduced.

During his final weeks in Europe, Trump conducted debriefing interviews with the leadership of Telefunken, the company that had developed Nazi Germany's radar. He learned that German radar development had fallen substantially behind, and attributed this to a lack of cooperation with scientists. Nazi industrialists did not work closely with physicists, and scientists were barred from accompanying equipment into combat.

Returning to MIT in April 1945, Trump was appointed assistant director of the Rad Lab and organized a new Field Service division to reproduce the BBRL model in the Pacific. He helped arrange a field radar operation in Manila at General MacArthur's request, but the effort ended with Japan's surrender.

Trump received recognition for his war service from both the United States and the United Kingdom. In 1947, King George VI awarded Trump the Medal for Service in the Cause of Freedom for his radar work and cooperation with Britain. A year later, President Truman awarded Trump the President's Certificate of Merit, given to 250 civilian scientists who "performed a meritorious act or service" during the war. MIT built a campus cancer treatment facility (Building 28) around a Van de Graaff accelerator of Trump's design. Over the next 22 years, over 500 cancer patients a year received treatment at MIT using Trump's x-ray generator. Trump supervised treatments and research on tumor targeting, including a novel "rotational radiation therapy" technique that moved the patient around a fixed beam. For many years, he taught radiation physics courses to early-career radiologists. The lab also focused on skin cancer treatment, designing a 5-MV electron-beam generator for targeting superficial lesions. HVEC's first product was a commercial version of Trump's compact 2 MV generator, which could be operated by hospital technicians. It provided controllable, directed radiation that reduced damage to healthy tissue compared to traditional radium sources. Between 1948 and 1969, HVEC delivered these machines to 35 U.S. hospitals and eight hospitals abroad.

Trump's MIT lab also maintained close ties with HVEC. The High Voltage Research Laboratory provided technical feedback, developed clinical procedures, and tested prototypes for the company. While HVEC's Van de Graaff accelerators were early market leaders in radiotherapy, cheaper cobalt-60 machines and higher-voltage medical linear accelerators debuted in the 1950s, displacing HVEC's Van de Graaff accelerators as the preferred source for radiotherapy.

As federal funding for nuclear physics expanded, HVEC pivoted from medical devices to large research accelerators for universities and national laboratories. Trump and Van de Graaff contributed technical innovations that enabled higher-voltage machines. Between 1958 and 1973, HVEC manufactured 55 tandem accelerators that became the dominant platform for nuclear physics experiments. At its peak, nearly 70 percent of papers in experimental nuclear physics relied on data from HVEC accelerators.

At the time of its 1963 public offering, HVEC was ARD's largest asset and the first company it introduced to public markets. Along with Ionics, it established ARD's focus on research-intensive ventures. This approach anticipated ARD's later investment in Digital Equipment Corporation, considered the first "home run" of venture capital industry.

HVEC invested heavily in higher-energy accelerators with the potential to fuse superheavy elements. When federal support for nuclear physics retreated in 1969, its research accelerator business collapsed. Trump exited his position as chairman in 1970, but continued providing technical advice over the next decade. The company reorganized as a conglomerate focused on industrial radiation processing products. Under a new business model, Trump championed industrial and environmental uses of electron beam technology. In 1962, he encouraged the company to invest in new industrial applications of ionizing radiation. In the late 1970s, he led research into electron beam treatment of wastewater and sewage sludge, demonstrating that high-energy radiation could eliminate pathogens and organic contaminants. In 1980, HVEC received contracts from Miami-Dade County and the Massachusetts Metropolitan District Commission to develop commercial-scale water treatment systems.

HVEC was privately purchased in 1988 and filed for bankruptcy in 2005. Trump held HVEC shares until his death in 1985.

Wastewater experiments In 1972, Congress passed new Clean Water Act standards for secondary treatment of wastewater discharged into oceans and waterways. New rules gave cities five years to make major upgrades to sewage treatment. Trump, who had longstanding interests in sterilization methods, initiated a new program at MIT concentrated on disinfecting wastewater. He researched using an electron beam from a 2-MeV accelerator as the deactivating agent in the treatment of municipal wastewater sludge. The High Voltage Research Laboratory developed a prototype system that was tested at Boston's Deer Island Waste Water Treatment Plant, and it was able to provide bacterial and viral disinfection via continuous on-line treatment.

Trump retired from his faculty appointment in 1973, but continued running wastewater experiments and teaching MIT students as a senior lecturer.

Science education Trump became a trustee of the Boston Museum of Science in 1961. When the museum installed the original Van de Graaff generator as a permanent exhibition, he designed electrostatic shielding that allowed live audience demonstrations. He became a life trustee of the museum.

Legacy President Ronald Reagan awarded Trump the National Medal of Science in 1983 for his innovative applications of radiation in medicine, industry and atomic physics. Trump died six days before the White House ceremony in February 1985, and his son John, Jr. accepted the medal on his behalf. In a posthumous tribute, the National Academy of Engineering described John Trump as "a pioneer in the scientific, engineering and medical applications of high voltage machinery."

In addition to his cancer research, Trump made institutional contributions to the Lahey Clinic. While chair of its board, he advocated for the relocation of the cancer clinic to a new hospital campus in Burlington, Massachusetts. The radiation oncology building of the Lahey Hospital & Medical Center is named for Trump. In 2024, one of his scientific collaborators endowed a fund at Lahey for diagnostic radiation named for Trump.

Disputed claims about career Refusal to work on weaponry James Melcher, Trump's successor as HVRL director, falsely claimed that Trump declined to research military weaponry during his career. Melcher, an advocate for nuclear disarmament, stated: "John, over a period of three decades, would be approached by people of all sorts because he could make megavolt beams of ions and electrons – death rays... What did he do with it? Cancer research, sterilizing sludge out in Deer Island, all sorts of wondrous things. He didn't touch the weapons stuff." However, alongside his work in cancer research and sludge sterilization, Trump did work under military contracts for dual uses of microwave radar and high-voltage generators.

Longest-serving MIT professor President Donald Trump has repeatedly claimed his uncle was MIT's "longest serving professor." John Trump served as an MIT professor for 37 years (1936–1973), retiring at the university's then-mandatory retirement age of 65. His career at MIT spanned 51 years, including research staff and senior lecturer appointments before and after his professorship.

Alleged connections to the Unabomber At a July 2025 political rally, President Trump asserted that domestic terrorist Ted Kaczynski was Professor Trump's student. He described asking his uncle about Kaczynski's performance as a student. Because the reclusive Kaczynski was identified as the Unabomber in 1996, nine years after John Trump's death, multiple media outlets concluded it was unlikely President Trump knew the Unabomber's identity during his uncle's lifetime. Kaczynski was a student at Harvard University (1959–62) and the University of Michigan (1962–67); MIT officials told CNN they have no records of Kaczynski's enrollment in MIT courses. The Trumps had three children: John Gordon Trump (1938–2012) of Watertown, Massachusetts; Christine Philp (1942–2021) of New London, New Hampshire; and Karen Ingraham of Los Alamos, New Mexico; and six grandchildren.

The Trumps lived in Winchester, Massachusetts, and were members of the Winchester Unitarian Society.

Awards and honors Trump received a number of awards including: 1947: The King's Medal for Service in the Cause of Freedom (KMS), given by George VI 1960: The Lamme Medal, given by the American Institute of Electrical Engineers 1982: American College of Radiology Gold Medal 1983: The National Medal of Science for Engineering Sciences

Selected publications Trump wrote about 100 peer-reviewed articles, published across journals in applied physics, nuclear science, radiology and medicine, scientific instruments, and environmental engineering.

Dissertation

Journal articles

Essays

Reports

Manuscripts A War Diary, 1944-5 (1973)