Dingell was one of the final two World War II veterans to have served in Congress; the other was Texas Representative Ralph Hall.

He rose to the rank of second lieutenant and received orders to take part in the first wave of a planned invasion of Japan in November 1945; the Congressman said that President Harry S. Truman's decision to use the atomic bomb to end the war saved his life.

Dingell always won re-election by double-digit margins, although the increasing conservatism of the mostly white suburbs of Detroit since the 1970s led to several serious Republican challenges in the 1990s.

[27][better source needed] Throughout his career he was a leading congressional supporter of organized labor, social welfare measures and traditional progressive policies.

[29] While he supported all of the civil rights bills, he opposed expanding school desegregation to Detroit suburbs via mandatory busing.

[32] As well, in the early 1980s, he was a prominent politician who used "Japan bashing", blaming "little yellow men" for domestic automakers' misfortune, further fostering anti-Japanese racism in Detroit and contributing to the environment that led to the Killing of Vincent Chin, an American man of Chinese descent killed in the Detroit suburbs by two autoworkers who mistakenly thought he was Japanese.

[33] An avid sportsman and hunter, he strongly opposed gun control, and was a former board member of the National Rifle Association of America.

My father worked on Social Security and for national health insurance, and I sat in the chair and presided over the House as Medicare passed (in 1965).

[37] On December 15, 2005, on the floor of the House, Dingell read a poem sharply critical of, among other things, Fox News, Bill O'Reilly, and the so-called "War on Christmas".

[38] Along with John Conyers, in April 2006, Dingell brought an action against George W. Bush and others alleging violations of the Constitution in the passing of the Deficit Reduction Act of 2005.

[39] After winning re-election in 2008 for his 28th consecutive term, Dingell surpassed the record for having the longest tenure in the history of the House of Representatives on February 11, 2009.

[40] In honor of the record, Michigan Governor Jennifer Granholm declared February 11, 2009, to be John Dingell Day.

[41] Dingell was one of the final two World War II veterans to have served in Congress; the other was Texas Representative Ralph Hall.

According to Newsweek, he had wanted to investigate the George W. Bush Administration's handling of port security, the Medicare prescription drug program and Dick Cheney's energy task force.

[51] Time magazine has stated that he had intended to oversee legislation that addresses global warming and climate change caused by carbon emissions from automobiles, energy companies and industry.

[52] Dingell lost the chairmanship for the 111th Congress to Congressman Henry Waxman of California in a Democratic caucus meeting on November 20, 2008.

Dingell was given the title of Chairman Emeritus in a token of appreciation of his years of service on the committee, and a portrait of him is in the House collection.

[53] In the 1980s, Dingell led a series of congressional hearings to pursue alleged scientific fraud by Thereza Imanishi-Kari and Nobel Prize-winner David Baltimore.

The National Institutes of Health's fraud unit, then called the Office of Scientific Integrity, charged Imanishi-Kari in 1991 of falsifying data and recommended that she be barred from receiving research grants for 10 years.

[59][60] The report concluded that Gallo had engaged in fraud and that the NIH covered up his misappropriation of work by the French team at the Institut Pasteur.

In November 2007, working with House Speaker Nancy Pelosi, Dingell helped draft an energy bill that would mandate 40% increase in fuel efficiency standards.

[68] In June 1999, Dingell released a report in which the General Accounting Office cited concurrent design and construction was the reason for production of high levels of explosive benzene gas.

In a statement, Dingell asserted that "mismanagement by the United States Department of Energy and Westinghouse led to an extraordinary, and pathetic, waste of taxpayer money.

"[69] In July 2007, Dingell indicated he planned to introduce a new tax on carbon usage in order to curtail greenhouse gas emissions.

[73] Dingell also held an unknown quantity, more than $1 million in 2005,[74] in assets through General Motors stock options and savings-stock purchase programs; his wife, Debbie Dingell, is a descendant of one of the Fisher brothers, founders of Fisher Body, a constituent part of General Motors.

In November 2014, Debbie Dingell won the election to succeed her husband as U.S. Representative for Michigan's 12th congressional district.

[84] In his later years, Dingell became an active Twitter user, and earned over 250,000 followers for his witty and sarcastic posts attacking Republicans, particularly Donald Trump.