[1] Cabot was named after Thomas Dudley, the governor of Massachusetts Bay Colony who signed the charter creating Harvard College.

[9] He took some courses at Boston Tech (now known as Massachusetts Institute of Technology)[1] and Curtiss Flying School,[10] becoming a World War I flight instructor at Kelly Field in the U.S. Army Signal Corps,[3] before graduating cum laude from Harvard University with a SB in Engineering, in 1919.

He was CEO of Cabot Corporation from 1922 to 1960, when he relinquished active control of the company,[2] and went to his Boston office as director emeritus on a regular basis until his death.

[1] Cabot was also a longtime director of United Fruit Company, and became its president in 1948 in hopes of reformation, but resigned in 1949.

[13] In 1951, Cabot was U.S. Department of State's Director of Office of International Security Affairs during the Truman administration,[1] where he spoke for the State Department on NATO affairs, was in charge of a U.S. program arming allies throughout the world,[4] and supervised the disbursement of $6 billion in foreign economic and military aid.

[4] In 1960, a Central Intelligence Agency cover[14] called Gibraltar Steamship Company (which didn't own any steamships and whose president was Cabot)[15][16] owned and established Radio Swan on Swan Island, a covert black operation[15] to win supporters for U.S. policies and discredit Fidel Castro.

[20] He and his wife established the Thomas D. and Virginia W. Cabot chair, in 1986, following his family's legacy of MIT involvement.