Ingersoll was Chief executive officer and chairman of the Board of BorgWarner and his international business experience was an important factor in his selection as United States Ambassador to Japan from 1972 to 1973, and assistant Secretary of State for East Asian and Pacific Affairs from 1973 to 1974, both during President Richard Nixon's term in office.

[1] he attended the Phillips Academy in Andover, Massachusetts and graduated from the Sheffield Scientific School at Yale University in 1937.

Shifting to foreign car companies as U.S. domestic manufacturers bought production in house, by 1971 Ingersoll saw automobile transmission sales increase more than tenfold to 487,000 units in the preceding decade.

[5] After the Lockheed bribery scandals were disclosed to the public, Ingersoll played a lead role in the State Department's handling of the affair, which he stated had done "grievous damage" to U.S. foreign relations, with Lockheed having paid $3 million in bribes to the office of Japanese Prime Minister Kakuei Tanaka and more than $1 million in improper payments to Prince Bernhard of the Netherlands.

[2] Ingersoll was former chairman of the Panasonic Foundation and also served as the vice president of the board of directors of the United States Chamber of Commerce.