Google confronts an existential threat Monday as the U.S. government tries to break up the company as punishment for turning its revolutionary search engine into a ruthless monopoly.

Alphabet's Google needs strong measures imposed on it to prevent it from using its artificial intelligence products to extend its dominance in online search, a U.S. Department of Justice attorney said as a trial in the historic antitrust case began on Monday.

After a federal judge ruled that Google had a monopoly on the search market, the tech giant and the government are in court to debate penalties. One possible result: forcing Google to spin off Chrome.