 During the early years of television , there was some measure of cooperation among the four major U.S. television networks . However , as television grew into a profitable business , an intense rivalry developed between the networks , just as it had in radio . NBC and CBS competed fiercely for viewers and advertising dollars , a contest neither <unk> DuMont nor ABC could hope to win . According to author Dennis <unk> , " NBC tried to make an arrangement with ABC and CBS to destroy the DuMont network . " The plan was for NBC and CBS to exclusively offer ABC their most popular series after they had aired on the bigger networks . ABC would become a network of re @-@ runs , but DuMont would be shut out . ABC president Leonard Goldenson rejected NBC executive David <unk> 's proposal , but " did not report it to the Justice Department " . 
