Bill gains senate approval but must still be passed by the House of Representatives before being presented to Joe Biden
A bill introduced last year proposed making it a legal requirement for large tech firms to build a backdoor into their devices
And it only took them three years
Hearing comes a month after US Congress House Antitrust Subcommittee grilled chief executives of Facebook, Google, Apple and Amazon
New law is intended to crack down on alleged espionage by China against US infrastructure and intellectual property