John Glenn

John Herschel Glenn Jr. was born on July 18, 1921, in Cambridge, Ohio, the son of John Herschel Glenn Sr. (1895–1966), who worked for a plumbing firm, and Clara Teresa (née Sproat; 1897–1971), a teacher. His parents had married shortly before John Sr., a member of the American Expeditionary Force, left for the Western Front during World War I. The family moved to New Concord, Ohio, soon after his birth, and his father started his own business, the Glenn Plumbing Company. Glenn Jr. was only a toddler when he met Anna Margaret (Annie) Castor, whom he would later marry. The two would not be able to recall a time when they did not know each other. He first flew in an airplane with his father when he was eight years old. He became fascinated by flight, and built model airplanes from balsa wood kits. Along with his adopted sister Jean, he attended New Concord Elementary School. He washed cars and sold rhubarb to earn money to buy a bicycle, after which he took a job delivering The Columbus Dispatch newspaper. He was a member of the Ohio Rangers, an organization similar to the Cub Scouts. His boyhood home in New Concord has been restored as a historic house museum and education center.

Glenn attended New Concord High School, where he played on the varsity football team as a center and linebacker. He also made the varsity basketball and tennis teams, and was involved with Hi-Y, a junior branch of the YMCA. After graduating in 1939, Glenn entered Muskingum College, where he studied chemistry, joined the Stag Club fraternity, and played on the football team. Annie majored in music with minors in secretarial studies and physical education and competed on the swimming and volleyball teams. Glenn earned a private pilot license and a physics course credit for free through the Civilian Pilot Training Program in 1941. He did not complete his senior year in residence or take a proficiency exam, both required by the school for its Bachelor of Science degree.

When the United States entered World War II, Glenn quit college to enlist in the U.S. Army Air Corps. He was not called to duty by the Army, and enlisted as a U.S. Navy aviation cadet in March 1942. Glenn attended the University of Iowa in Iowa City for pre-flight training and made his first solo flight in a military aircraft at Naval Air Station Olathe in Kansas, where he went for primary training. During advanced training at Naval Air Station Corpus Christi in Texas, he accepted an offer to transfer to the U.S. Marine Corps. Having completed his flight training in March 1943, Glenn was commissioned as a second lieutenant. After advanced training at Camp Kearny, California, he was assigned to Marine Squadron VMJ-353, which flew R4D transport planes from there. Glenn married Annie in a Presbyterian ceremony at College Drive Church in New Concord, Ohio, on April 6, 1943.

The fighter squadron VMO-155 was also at Camp Kearny flying the Grumman F4F Wildcat. Glenn approached the squadron's commander, Major J. P. Haines, who suggested that he could put in for a transfer. This was approved, and Glenn was posted to VMO-155 on July 2, 1943, two days before the squadron moved to Marine Corps Air Station El Centro in California. The Wildcat was obsolete by this time, and VMO-155 re-equipped with the F4U Corsair in September 1943. He was promoted to first lieutenant in October 1943, and shipped out to Hawaii in January 1944. VMO-155 became part of the garrison on Midway Atoll on February 21, then moved to the Marshall Islands in June 1944 and flew 57 combat missions in the area. He received two Distinguished Flying Crosses and ten Air Medals.

At the end of his one-year tour of duty in February 1945, Glenn was assigned to Marine Corps Air Station Cherry Point in North Carolina, then to Naval Air Station Patuxent River in Maryland. He was promoted to captain in July 1945 and ordered back to Cherry Point. There, he joined VMF-913, another Corsair squadron, and learned that he had qualified for a regular commission. In March 1946, he was assigned to Marine Corps Air Station El Toro in southern California. He volunteered for service with the occupation in North China, believing it would be a short tour. He joined VMF-218 (another Corsair squadron), which was based at Nanyuan Field near Beijing, in December 1946, and flew patrol missions until VMF-218 was transferred to Guam in March 1947.

In December 1948, Glenn was re-posted to NAS Corpus Christi as a student at the Naval School of All-Weather Flight before becoming a flight instructor. In July 1951, he traveled to the Amphibious Warfare School at Marine Corps Base Quantico in northern Virginia for a six-month course. He then joined the staff of the commandant of the Marine Corps Schools. He maintained his proficiency (and flight pay) by flying on weekends due to only being given four hours of flying time per month. He was promoted to major in July 1952. Glenn received the World War II Victory Medal, American Campaign Medal, Asiatic-Pacific Campaign Medal (with one star), Navy Occupation Service Medal (with Asia clasp), and the China Service Medal for his efforts.

Glenn moved his family back to New Concord during a short period of leave, and after two and a half months of jet training at Cherry Point, was ordered to South Korea in October 1952, late in the Korean War. Before he set out for Korea in February 1953, he applied to fly the F-86 Sabre jet fighter-interceptor through an inter-service exchange position with the U.S. Air Force (USAF). In preparation, he arranged with Colonel Leon W. Gray to check out the F-86 at Otis Air Force Base in Massachusetts. Glenn reported to K-3, an airbase in South Korea, on February 3, 1953, and was assigned to be the operations officer for VMF-311, one of two Marine fighter squadrons there while he waited for the exchange assignment to go through. VMF-311 was equipped with the F9F Panther jet fighter-bomber. Glenn's first mission was a reconnaissance flight on February 26. He flew 63 combat missions in Korea with VMF-311, and was nicknamed "Magnet Ass" because of the number of flak hits he took on low-level close air support missions; twice, he returned to base with over 250 holes in his plane. He flew for a time with Marine reservist Ted Williams (a future Hall of Fame baseball player with the Boston Red Sox) as his wingman. Williams later said about Glenn "Absolutely fearless. The best I ever saw. It was an honor to fly with him." Glenn also flew with future major general Ralph H. Spanjer.

In June 1953, Glenn reported for duty with the USAF's 25th Fighter-Interceptor Squadron, and flew 27 combat missions in the F-86, a much faster aircraft than the F9F Panther, patrolling MiG Alley. Combat with a MiG-15, which was faster and better armed still, was regarded as a rite of passage for a fighter pilot. On the Air Force buses that ferried the pilots out to the airfields before dawn, pilots who had engaged a MiG could sit while those who had not had to stand. Glenn later wrote, "Since the days of the Lafayette Escadrille during World War I, pilots have viewed air-to-air combat as the ultimate test not only of their machines but of their own personal determination and flying skills. I was no exception." He hoped to become the second Marine jet flying ace after John F. Bolt. Glenn's USAF squadron mates painted "MiG Mad Marine" on his aircraft when he complained about there not being any MIGs to shoot at. He shot down his first MiG in a dogfight on July 12, 1953, downed a second one on July 19, and a third on July 22 when four Sabres shot down three MiGs. These were the final air victories of the war, which ended with an armistice five days later. For his service in Korea, Glenn received two more Distinguished Flying Crosses and eight more Air Medals. Glenn also received the Korean Service Medal (with two campaign stars), United Nations Korea Medal, Marine Corps Expeditionary Medal, National Defense Service Medal (with one star), and the Korean War Service Medal.

With combat experience as a fighter pilot, Glenn applied for training as a test pilot while still in Korea. He reported to the U.S. Naval Test Pilot School at NAS Patuxent River in Maryland in January 1954, and graduated in July. At Patuxent River the future Medal of Honor recipient, James Stockdale tutored him in physics and math. Glenn's first flight test assignment, testing the FJ-3 Fury, nearly killed him when its cockpit depressurized and its oxygen system failed. He also tested the armament of aircraft such as the Vought F7U Cutlass and F8U Crusader. From November 1956 to April 1959, he was assigned to the Fighter Design Branch of the Navy Bureau of Aeronautics in Washington, D.C., and attended the University of Maryland.

On July 16, 1957, he made the first supersonic transcontinental flight. At that time, the transcontinental speed record, held by an Air Force Republic F-84 Thunderjet, was 3 hours 45 minutes and Glenn calculated that an F8U Crusader could do it faster. Because its 586-mile-per-hour (943 km/h) air speed was faster than that of a .45 caliber bullet, Glenn called his project Project Bullet. He flew an F8U Crusader 2,445 miles (3,935 km) from Los Alamitos, California to Floyd Bennett Field in New York City in 3 hours, 23 minutes and 8.3 seconds, averaging supersonic speed despite three in-flight refuelings when speeds dropped below 300 miles per hour (480 km/h). His on-board camera took the first continuous, transcontinental panoramic photograph of the United States. He received his fifth Distinguished Flying Cross for this mission, and was promoted to lieutenant colonel on April 1, 1959. His cross-country flight made him a minor celebrity. A profile piece appeared in The New York Times and he appeared on the television show Name That Tune. He now had nearly 9,000 hours of flying time, including about 3,000 hours in jets.

On October 4, 1957, the Soviet Union launched Sputnik 1, the first artificial satellite. This damaged American confidence in its technological superiority, creating a wave of anxiety known as the Sputnik crisis. In response, President Dwight D. Eisenhower launched the Space Race. The National Aeronautics and Space Administration (NASA) was established on October 1, 1958, as a civilian agency to develop space technology. One of its first initiatives was announced on December 17, 1958. This was Project Mercury, which aimed to launch a man into Earth orbit, return him safely to the Earth, and evaluate his capabilities in space.

NASA received permission from Eisenhower to recruit its first astronauts from the ranks of military test pilots. The service records of 508 graduates of test pilot schools were obtained from the United States Department of Defense. From these, 110 were found that matched the minimum standards: the candidates had to be younger than 40, possess a bachelor's degree or equivalent, and be 5 feet 11 inches (1.80 m) or less. Only the height requirement was strictly enforced, owing to the size of the Project Mercury spacecraft. This was fortunate for Glenn, who barely met the requirements, as he was near the age cutoff and lacked a science-based degree. The 110 were then split into three groups, with the most promising in the first group. The first group of 35, which included Alan Shepard, assembled at the Pentagon on February 2, 1959. The Navy and Marine Corps officers were welcomed by the Chief of Naval Operations, Admiral Arleigh Burke, and the USAF officers were addressed by the Chief of Staff of the United States Air Force, General Thomas D. White. Both pledged their support to the Space Program, and promised that the careers of volunteers would not be adversely affected. NASA officials then briefed them on Project Mercury. They warned that it would be a hazardous undertaking, but emphasized that it was of great national importance.

In 1961, Glenn received an honorary LL.D from Muskingum University, the college he attended before joining the military in World War II. He also received honorary doctorates from Nihon University in Tokyo; Wagner College in Staten Island, New York; Ohio Northern University; Williams College; and Brown University. In 1998 he helped found the John Glenn Institute for Public Service and Public Policy at Ohio State University to encourage public service. The institute merged with OSU's School of Public Policy and Management to become the John Glenn School of Public Affairs. He held an adjunct professorship at the school. In February 2015, it was announced that it would become the John Glenn College of Public Affairs in April.

Glenn remained an officer in the Marine Corps after his selection, and was assigned to the NASA Space Task Group at Langley Research Center in Hampton, Virginia. The task force moved to Houston, Texas, in 1962, and became part of the NASA Manned Spacecraft Center. A portion of the astronauts' training was in the classroom, where they learned space science. The group also received hands-on training, which included scuba diving and work in simulators. Astronauts secured an additional role in the spaceflight program: to provide pilot input in design. The astronauts divided the various tasks between them. Glenn's specialization was cockpit layout design and control functioning for the Mercury and early Apollo programs. He pressed the other astronauts to set a moral example, living up to the squeaky-clean image of them that had been portrayed by Life magazine, a position that was not popular with the other astronauts.

Glenn was the backup pilot for Shepard and Grissom on the first two crewed Project Mercury flights, the sub-orbital missions Mercury-Redstone 3 and Mercury-Redstone 4. Glenn was selected for Mercury-Atlas 6, NASA's first crewed orbital flight, with Carpenter as his backup. Putting a man in orbit would achieve one of Project Mercury's most important goals. Shepard and Grissom had named their spacecraft Freedom 7 and Liberty Bell 7. The numeral 7 had originally been the production number of Shepard's spacecraft, but had come to represent the Mercury 7. Glenn named his spacecraft, number 13, Friendship 7, and had the name hand-painted on the side like the one on his F-86 had been. Glenn and Carpenter completed their training for the mission in January 1962, but postponement of the launch allowed them to continue rehearsing. Glenn spent 25 hours and 25 minutes in the spacecraft performing hangar and altitude tests, and 59 hours and 45 minutes in the simulator. He flew 70 simulated missions and reacted to 189 simulated system failures.

After a long series of delays, Friendship 7 lifted off from Cape Canaveral Air Force Station on February 20, 1962. There were eleven delays during the countdown due to equipment malfunctions and improvements and the weather. During Glenn's first orbit, a failure of the automatic-control system was detected. This forced Glenn to operate in manual mode for the second and third orbits, and for re-entry. Later in the flight, telemetry indicated that the heat shield had loosened. If this reading had been accurate, Glenn and his spacecraft would have burned up on re-entry. After a lengthy discussion on how to deal with this problem, ground controllers decided that leaving the retrorocket pack in place might help keep the loose heat shield in place. They relayed these instructions to Glenn, but did not tell him the heat shield was possibly loose; although confused at this order, he complied. The retrorocket pack broke up into large chunks of flaming debris that flew past the window of his capsule during re-entry; Glenn thought this might have been the heat shield. He told an interviewer, "Fortunately it was the rocket pack—or I wouldn't be answering these questions." After the flight, it was determined that the heat shield was not loose; the sensor was faulty.

As the first American in orbit, Glenn became a national hero, met President John F. Kennedy, and received a ticker-tape parade in New York reminiscent of those honoring Charles Lindbergh and other heroes. He became "so valuable to the nation as an iconic figure", according to NASA administrator Charles Bolden, that Kennedy would not "risk putting him back in space again." Glenn's fame and political potential were noted by the Kennedys, and he became a friend of the Kennedy family. On February 23, 1962, President Kennedy gave him the NASA Distinguished Service Medal for his Friendship 7 flight. Upon receiving the award, Glenn said, "I would like to consider I was a figurehead for this whole big, tremendous effort, and I am very proud of the medal I have on my lapel." Glenn also received his sixth Distinguished Flying Cross for his efforts. He was among the first group of astronauts to be awarded the Congressional Space Medal of Honor. The award was presented to him by President Jimmy Carter in 1978. After his 1962 spaceflight, NASA proposed giving Glenn the Medal of Honor, but Glenn did not think that would be appropriate. His military and space awards were stolen from his home in 1978, and he remarked that he would keep this medal in a safe.

In 1962, NASA contemplated recruiting women to the astronaut corps, but Glenn gave a speech before the House Space Committee detailing his opposition to sending women into space, in which he said:

At 42, Glenn was the oldest member of the astronaut corps and would likely be close to 50 by the time the lunar landings took place. During Glenn's training, NASA psychologists determined that he was the astronaut best suited for public life. Attorney General Robert F. Kennedy suggested to Glenn and his wife in December 1962 that he run for the 1964 United States Senate election in Ohio, challenging aging incumbent Stephen M. Young (1889–1984) in the Democratic primary election. As it seemed unlikely that he would be selected for Project Apollo missions, he resigned from NASA on January 16, 1964, and announced his Democratic Party candidacy for the U.S. Senate from his home state of Ohio the following day, becoming the first astronaut-politician. Glenn was still a Marine, and had plenty of unused leave time. He elected to use it while he waited for his retirement papers to go through.

The Glenn Research Center at Lewis Field in Cleveland is named after him, and the Senator John Glenn Highway runs along a stretch of I-480 in Ohio across from the Glenn Research Center. Colonel Glenn Highway (which passes Wright-Patterson Air Force Base and Wright State University near Dayton, Ohio), John Glenn High School in his hometown of New Concord, and the former Col. John Glenn Elementary in Seven Hills, Ohio, were also named for him. Colonel Glenn Road in Little Rock, Arkansas, was named for him in 1962. High schools in Westland and Bay City, Michigan; Walkerton, Indiana; San Angelo, Texas, and Norwalk, California bear Glenn's name. The fireboat John H. Glenn Jr., operated by the District of Columbia Fire and Emergency Medical Services Department and protecting sections of the Potomac and Anacostia Rivers which run through Washington, D.C., was named for him, as was USNS John Glenn (T-MLP-2), a mobile landing platform delivered to the U.S. Navy on March 12, 2014. In June 2016, the Port Columbus International Airport in Columbus, Ohio, was renamed John Glenn Columbus International Airport. Glenn and his family attended the ceremony, during which he spoke about how visiting the airport as a child had kindled his interest in flying. On September 12, 2016, Blue Origin announced the New Glenn, a rocket. Orbital ATK named the Cygnus space capsule used in the NASA CRS OA-7 mission to the international space station "S.S. John Glenn" in his honor. The mission successfully lifted off on April 16, 2017.

Glenn was awarded the John J. Montgomery Award in 1963. Glenn received National Geographic Society's Hubbard Medal in 1962. Glenn, along with 37 other space race astronauts, received the Ambassador of Space Exploration Award in 2006. He was also awarded the General Thomas D. White National Defense Award, and the Prince of Asturias Award for International Cooperation. In 1964, Glenn received the Golden Plate Award of the American Academy of Achievement. In 2004, he received the Woodrow Wilson Award for Public Service from the Woodrow Wilson International Center for Scholars of the Smithsonian Institution, and was awarded the National Collegiate Athletic Association's Theodore Roosevelt Award for 2008.

NASA had no official policy prohibiting women, but the requirement that astronauts had to be test pilots effectively excluded them. NASA dropped this requirement in 1965, but did not select any women as astronauts until 1978, when six women were selected, none as pilots. In June 1963, the Soviet Union launched a female cosmonaut, Valentina Tereshkova into orbit. After Tereshkova, no women of any nationality flew in space again until August 1982, when the Soviet Union launched pilot-cosmonaut Svetlana Savitskaya. During the late 1970s, Glenn reportedly supported Space Shuttle Mission Specialist Judith Resnik in her career.

Glenn was still on leave from the Marine Corps, and he withdrew his papers to retire so he could keep a salary and health benefits. Glenn was on the list of potential candidates to be promoted to full colonel, but he notified the Commandant of the Marine Corps of his intention to retire so another Marine could receive the promotion. President Johnson later decided to promote Glenn to full colonel status, without taking someone else's spot. He retired as a colonel on January 1, 1965. Glenn was approached by RC Cola to join their public relations department, but Glenn declined it because he wanted to be involved with a business, and not just the face of it. The company revised their offer, and offered Glenn a vice president of corporate development position, as well as a place on the board of directors. The company later expanded Glenn's role, promoting him to president of Royal Crown International. A Senate seat was open in 1968, and Glenn was asked about his current political aspirations. He said he had no current plan, and "Let's talk about it one of these days." Glenn also said that a 1970 Senate run was a possibility.

Glenn remained close to the Kennedy family, and campaigned for Robert F. Kennedy during his 1968 presidential campaign. In 1968, Glenn was in Kennedy's hotel suite when Kennedy heard he had won California. Glenn was supposed to go with him to celebrate, but decided not to as there would be many people there. Kennedy went downstairs to make his victory speech and was assassinated. Glenn and Annie went with them to the hospital, and the next morning took Kennedy's children home to Virginia. Glenn was later a pallbearer at the funeral in New York.

In 1970, Young did not seek reelection and the seat was open. Businessman Howard Metzenbaum, Young's former campaign manager, was backed by the Ohio Democratic party and major labor unions, which provided him a significant funding advantage over Glenn. Glenn's camp persuaded him to be thrifty during the primary so he could save money for the general election. By the end of the primary campaign, Metzenbaum was spending four times as much as Glenn. Glenn was defeated in the Democratic primary by Metzenbaum (who received 51 percent of the vote to Glenn's 49 percent). Some prominent Democrats said Glenn was a "hapless political rube", and one newspaper called him "the ultimate square".

Metzenbaum lost the general election to Robert Taft Jr. Glenn remained active in the political scene following his defeat. John J. Gilligan, the Ohio Governor at the time, appointed Glenn to be the chairman of the Citizens Task Force on Environmental Protection in 1970. The task force was created to survey environmental problems in the state and released a report in 1971 detailing the issues. The meetings and the final report of the task force were major contributors to the formation of Ohio's Environmental Protection Agency.

Glenn's campaign changed their strategy after the 1970 election. In 1970, Glenn won most of the counties in Ohio but lost in those with larger populations. The campaign changed its focus, and worked primarily in the large counties. In the primary, Metzenbaum contrasted his strong business background with Glenn's military and astronaut credentials and said that his opponent had "never held a payroll". Glenn's reply became known as the "Gold Star Mothers" speech. He told Metzenbaum to go to a veterans' hospital and "look those men with mangled bodies in the eyes and tell them they didn't hold a job. You go with me to any Gold Star mother and you look her in the eye and tell her that her son did not hold a job". He defeated Metzenbaum 54 to 46 percent before defeating Ralph Perk (the Republican mayor of Cleveland) in the general election, beginning a Senate career which would continue until 1999.

In 1973, he and a friend bought a Holiday Inn near Disney World. The success of Disney World expanded to their business, and the pair built three more hotels. One of Glenn's business partners was Henri Landwirth, a Holocaust survivor who became his best friend. He remembered learning about Landwirth's background: "Henri doesn't talk about it much. It was years before he spoke about it with me and then only because of an accident. We were down in Florida during the space program. Everyone was wearing short-sleeved Ban-Lon shirts—everyone but Henri. Then one day I saw Henri at the pool and noticed the number on his arm. I told Henri that if it were me I'd wear that number like a medal with a spotlight on it."

In 1973, President Nixon ordered Attorney General Elliot Richardson to fire Watergate special prosecutor Archibald Cox. Richardson refused and resigned in protest, triggering the Saturday Night massacre. Ohio Senator William Saxbe, elected in 1968, was appointed attorney general. Both Glenn and Metzenbaum sought the vacated seat, which was to be filled by Governor John Gilligan. Gilligan was planning on a presidential or vice-presidential run in the near future, and offered Glenn the lieutenant governor position, with the thought that Glenn would ascend to governor when Gilligan was elected to a higher position. The Ohio Democratic party backed this solution to avoid what was expected to be a divisive primary battle between Metzenbaum and Glenn. He declined, denouncing their attempts as "bossism" and "blackmail". Glenn's counteroffer suggested that Gilligan fill the position with someone other than Metzenbaum or Glenn so neither would have an advantage going into the 1974 election. Metzenbaum's campaign agreed to back Gilligan in his governor re-election campaign, and Metzenbaum was subsequently appointed in January 1974 to the vacated seat. At the end of Saxbe's term, Glenn challenged Metzenbaum in the primary for the Ohio Senate seat.

In the 1976 presidential election, Jimmy Carter was the presumptive Democratic nominee for president. Glenn was reported to be in consideration for the vice-presidential nomination because he was a senator in a pivotal state and for his fame and straightforwardness. Some thought he was too much like Carter, partially because they both had military backgrounds, and that he did not have enough experience to become president. Barbara Jordan was the first keynote speaker at the Democratic National Convention. Her speech electrified the crowd, and was filled with applause and standing ovations. Glenn's keynote address immediately followed Jordan's, and he failed to impress the delegates. Walter Cronkite described it as "dull", and other delegates complained that he was hard to hear. Carter called Glenn to inform him the nomination was going to another candidate, and later nominated the veteran politician Walter Mondale. It was also reported that Carter's wife thought Annie Glenn, who had a stutter, would hurt the campaign.

Glenn requested to be assigned to two committees during his first year as senator: the Government Operations Committee (later known as the Committee on Governmental Affairs), and the Foreign Relations Committee. He was immediately assigned to the Government Operations Committee, and waited for a seat on the Foreign Relations Committee. In 1977, Glenn wanted to chair the Energy, Nuclear Proliferation, and Federal Services Subcommittee of the Governmental Affairs Committee. Abraham Ribicoff, chair of the Governmental Affairs Committee, said he could chair the subcommittee if he also chaired the less popular Federal Services Subcommittee, which was in charge of the U.S. Postal Service. Previous chairs of the Federal Services Subcommittee lost elections due in part to negative campaigns that tied in the poorly regarded mail service with the chairmen, but Glenn accepted the offer and became the chair of both subcommittees. One of his goals as a new senator was developing environmental policies. Glenn introduced bills on energy policy to try to counter the energy crisis in the 70s. Glenn also introduced legislation promoting nuclear non-proliferation, and was the chief author of the Nuclear Non-Proliferation Act of 1978, the first of six major pieces of legislation that he produced on the subject.

Glenn joined the Foreign Relations Committee in 1978. He became the chairman of the East Asian and Pacific Affairs Subcommittee, for which he traveled to Japan, Korea, the Republic of China, and the People's Republic of China. Glenn helped to pass the Taiwan Enabling Act of 1979. The same year, Glenn's stance on the SALT II treaty caused another dispute with President Carter. Due to the loss of radar listening posts in Iran, Glenn did not believe that the U.S. had the capability to monitor the Soviet Union accurately enough to verify compliance with the treaty. During the launching ceremony for the USS Ohio, he spoke about his doubts about verifying treaty compliance. First Lady Rosalynn Carter also spoke at the event, during which she criticized Glenn for speaking publicly about the issue. The Senate never ratified the treaty, in part because of the Soviet invasion of Afghanistan. Glenn served on the committee until 1985, when he traded it for the Armed Services Committee.

A Freemason, Glenn was a member of Concord Lodge No. 688 in New Concord, Ohio. He received all his degrees in full in a Mason at Sight ceremony from the Grand Master of Ohio in 1978, 14 years after petitioning his lodge. In 1999, Glenn became a 33rd-degree Scottish Rite Mason in the Valley of Cincinnati (NMJ). As an adult, he was honored as part of the DeMolay Legion of Honor by DeMolay International, a Masonic youth organization for boys.

Glenn was unhappy with how divided the country was, and thought labels like conservative and liberal increased the divide. He considered himself a centrist. Glenn thought a more centrist president would help unite the country. Glenn believed his experience as a senator from Ohio was ideal, due to the state's diversity. Glenn thought that Ted Kennedy could win the election, but after Kennedy's announcement in late 1982 that he would not seek the presidency, Glenn thought he had a much better chance of winning. He hired a media consultant to help him with his speaking style.

Glenn announced his candidacy for president on April 21, 1983, in the John Glenn High School gymnasium. He started out the campaign out-raising the front-runner, Mondale. He also polled the highest of any Democrat against Reagan. During the fall of 1983, The Right Stuff, a film about the Mercury Seven astronauts, was released. Reviewers saw Ed Harris' portrayal of Glenn as heroic and his staff began to publicize the film to the press. One reviewer said that "Harris' depiction helped transform Glenn from a history-book figure into a likable, thoroughly adoration-worthy Hollywood hero," turning him into a big-screen icon. Others considered the movie to be damaging to Glenn's campaign, serving as only a reminder that Glenn's most significant achievement had occurred decades earlier. Glenn's autobiography said the film "had a chilling effect on the campaign."

Glenn's campaign decided to forgo the traditional campaigning in early caucuses and primaries, and focus on building campaign offices across the country. He opened offices in 43 states by January 1984. Glenn's campaign spent a significant amount of money on television advertising in Iowa, and Glenn chose not to attend an Iowan debate on farm issues. He finished fifth in the Iowa caucus, and went on to lose New Hampshire. Glenn's campaign continued into Super Tuesday, and he lost there as well. He announced his withdrawal from the race on March 16, 1984. After Mondale defeated him for the nomination, Glenn carried $3 million in campaign debt for over 20 years before receiving a reprieve from the Federal Election Commission.

With the primary complete, Glenn began his campaign against Kindness. Glenn believed he and other Democrats were the targets of a negative campaign thought up by the GOP strategists in Washington. Kindness focused on Glenn's campaign debts for his failed presidential run, and the fact he stopped payments on it while campaigning for the Senate seat. After winning the race with 62% of the vote, Glenn remarked, "We proved that in 1986, they couldn't kill Glenn with Kindness."

After the Challenger accident in 1986, Glenn criticized putting a "lay person in space for the purpose of gaining public support . . . while the shuttle is still in its embryonic stage". He supported flying research scientists. In 1995, Glenn read Space Physiology and Medicine, a book written by NASA doctors. He realized that many changes that occur to physical attributes during space flight, such as loss of bone and muscle mass and blood plasma, are the same as changes that occur due to aging. Glenn thought NASA should send an older person on a shuttle mission, and that it should be him. Starting in 1995, he began lobbying NASA director Dan Goldin for the mission. Goldin said he would consider it if there was a scientific reason, and if Glenn could pass the same physical examination the younger astronauts took. Glenn performed research on the subject, and passed the physical examination. On January 16, 1998, NASA Administrator Dan Goldin announced that Glenn would be part of the STS-95 crew; this made him, at age 77, the oldest person to fly in space.

Glenn became chairman of the Manpower Subcommittee of the Armed Services Committee in 1987. He introduced legislation such as increasing pay and benefits for American troops in the Persian Gulf during the Gulf War. He served as chairman until 1993, becoming chairman of the Armed Services Subcommittee on Military Readiness and Defense Infrastructure.

In 1992, Republican Mike DeWine won the Republican primary and challenged Glenn in the Senate election. Glenn ran unopposed in the primary. DeWine's campaign focused on the need for change and for term limits for senators. This would be Glenn's fourth term as senator. DeWine also criticized Glenn's campaign debts, using a bunny dressed as an astronaut beating a drum, with an announcer saying, "He just keeps owing and owing and owing", a play on the Energizer Bunny. During a debate, Glenn asked DeWine to stop his negative campaign ads, saying "This has been the most negative campaign". DeWine responded that he would if Glenn would disclose how he spent the money he received from Charles Keating, fallout from Glenn being named one of the Keating Five. Glenn won the Senate seat, with 2.4 million votes to DeWine's 2 million votes. It was DeWine's first-ever campaign loss. DeWine later worked on the intelligence committee with Glenn and watched his second launch into space.

The Ethics Committee's outside counsel, Robert Bennett, wanted to eliminate Republican senator John McCain and Glenn from the investigation. The Democrats did not want to exclude McCain, as he was the only Republican being investigated, which means they could not excuse Glenn from the investigation either. McCain and Glenn were reprimanded the least of the five, as the Senate commission found that they had exercised "poor judgment". The GOP focused on Glenn's "poor judgement" rather than what Glenn saw as complete exoneration. GOP chairman Robert Bennett said, "John Glenn misjudged Charles Keating. He also misjudged the tolerance of Ohio's taxpayers, who are left to foot the bill of nearly $2 billion." After the Senate's report, Glenn said, "They so firmly put this thing to bed ... there isn't much there to fuss with. I didn't do anything wrong." In his autobiography, Glenn wrote, "outside of people close to me dying, these hearings were the low point of my life." The case cost him $520,000 in legal fees. The association of his name with the scandal made Republicans hopeful that he could be defeated in the 1992 campaign, but Glenn defeated Lieutenant Governor Mike DeWine to retain his seat.

In 1995 Glenn became the ranking minority member of the Committee on Governmental Affairs. Glenn disputed the focus on illegal Chinese donations to the Democrats, and asserted that Republicans also had egregious fundraising issues. The committee chair, Fred Thompson of Tennessee, disagreed and continued the investigation. Thompson and Glenn continued to work together poorly for the duration of the investigation. Thompson would give Glenn only information he was legally required to. Glenn would not authorize a larger budget and tried to expand the scope of the investigation to include members of the GOP. The investigation concluded with a Republican-written report, which Thompson described as, "... a lot of things strung together that paint a real ugly picture." The Democrats, led by Glenn, said the report "... does not support the conclusion that the China plan was aimed at, or affected, the 1996 presidential election."

Glenn was the vice chairman of the Permanent Subcommittee on Investigations, a subcommittee of the Committee on Governmental Affairs. When the Republican Party regained control of the Senate in 1996, Glenn became the ranking minority member on the Permanent Subcommittee on Investigations until he was succeeded by Carl Levin. During this time, the committee investigated issue such as fraud on the Internet, mortgage fraud, and day trading of securities.

On February 20, 1997, which was the 35th anniversary of his Friendship 7 flight, Glenn announced that his retirement from the Senate would occur at the end of his term in January 1999. Glenn retired due to his age, saying "... there is still no cure for the common birthday".

NASA and the National Institute of Aging (NIA) planned to use Glenn as a test subject for research, with biometrics taken before, during and after his flight. Some experiments (in circadian rhythms, for example) compared him with the younger crew members. In addition to these tests, he was in charge of the flight's photography and videography. Glenn returned to space on the Space Shuttle on October 29, 1998, as a payload specialist on Space Shuttle Discovery. Shortly before the flight, researchers disqualified Glenn from one of the flight's two major human experiments (on the effect of melatonin) due to undisclosed medical reasons; he participated in experiments on sleep monitoring and protein use. On November 6, President Bill Clinton sent a congratulatory email to Glenn aboard the Discovery. This is often cited as the first email sent by a sitting US president, but records exist of emails being sent by President Clinton several years earlier.

Glenn was an honorary member of the International Academy of Astronautics and a member of the Society of Experimental Test Pilots, Marine Corps Aviation Association, Order of Daedalians, National Space Club board of trustees, National Space Society board of governors, International Association of Holiday Inns, Ohio Democratic Party, State Democratic Executive Committee, Franklin County (Ohio) Democratic Party and the 10th District (Ohio) Democratic Action Club. In 2001 he guest-starred as himself on the American television sitcom Frasier.

On September 5, 2009, John and Annie Glenn dotted the "i" in Ohio State University's Script Ohio marching band performance during the Ohio State–Navy football-game halftime show, which is normally reserved for veteran band members. To commemorate the 50th anniversary of the Friendship 7 flight on February 20, 2012, he had an unexpected opportunity to speak with the orbiting crew of the International Space Station when he was onstage with NASA Administrator Charlie Bolden at Ohio State University. On April 19, 2012, Glenn participated in the ceremonial transfer of the retired Space Shuttle Discovery from NASA to the Smithsonian Institution for permanent display at the Steven F. Udvar-Hazy Center. He used the occasion to criticize the "unfortunate" decision to end the Space Shuttle program, saying that grounding the shuttles delayed research.

Glenn earned the Navy's astronaut wings and the Marine Corps' Astronaut Medal. He was awarded the Congressional Gold Medal in 2011 and was among the first group of astronauts to be granted the distinction. In 2012, President Barack Obama presented Glenn with the Presidential Medal of Freedom. Glenn was the seventh astronaut to receive this distinction. The Congressional Gold Medal and the Presidential Medal of Freedom are considered the two most prestigious awards that can be bestowed on a civilian. The Society of Experimental Test Pilots awarded Glenn the Iven C. Kincheloe award in 1963, and he was inducted into the International Air & Space Hall of Fame in 1968, National Aviation Hall of Fame in 1976, the International Space Hall of Fame in 1977, and the U.S. Astronaut Hall of Fame in 1990. In 2000, he received the U.S. Senator John Heinz Award for public service by an elected or appointed official, one of the annual Jefferson Awards.

In a 2012 interview, Glenn said he regretted that NASA did not continue its research on aging by sending additional elderly people into space. After STS-95 returned safely, its crew received a ticker-tape parade. On October 15, 1998, NASA Road 1 (the main route to the Johnson Space Center) was temporarily renamed John Glenn Parkway for several months. Glenn was awarded the NASA Space Flight Medal in 1998 for flying on STS-95. In 2001, Glenn opposed sending Dennis Tito, the world's first space tourist, to the International Space Station because Tito's trip had no scientific purpose.

Glenn was in good health for most of his life. He retained a private pilot's license until 2011 when he was 90. In June 2014, Glenn underwent successful heart valve replacement surgery at the Cleveland Clinic. In early December 2016, he was hospitalized at the James Cancer Hospital of Ohio State University Wexner Medical Center in Columbus. According to a family source, Glenn had been in declining health, and his condition was grave; his wife and their children and grandchildren were at the hospital.

Glenn died on December 8, 2016, at the OSU Wexner Medical Center; he was 95 years old. No cause of death was disclosed. After his death, his body lay in state at the Ohio Statehouse. There was a memorial service at Mershon Auditorium at Ohio State University. Another memorial service was performed at Kennedy Space Center near the Heroes and Legends building. His body was interred at Arlington National Cemetery on April 6, 2017. At the time of his death, John Glenn was the last surviving member of the Mercury Seven.

The phrase "Godspeed, John Glenn", which fellow Mercury astronaut Scott Carpenter used to hail Glenn's launch into space, became his social-media hashtag: #GodspeedJohnGlenn. Former and current astronauts added tributes; so did NASA Administrator and former shuttle astronaut Charles Bolden, who wrote: "John Glenn's legacy is one of risk and accomplishment, of history created and duty to country carried out under great pressure with the whole world watching." President Obama ordered flags to be flown at half-staff until Glenn's burial. On April 5, 2017, President Donald Trump issued presidential proclamation 9588, titled "Honoring the Memory of John Glenn".