China has sold us such a fuckton of backdoored technology over the years that the only plausible reason this never happ'd sooner is corruption. They were buying linksys modems from us in the early 2000s and selling em back to us w/ hardware level backdoors in em. You'd have to take one apart and compare it to the specs on diagrams to find what they did.
They did the same with datacenter gear (Cisco) was a major target of that too.
The gov created a special "secret" office just to randomly pull hardware that was bought new or already operating to do forensics on it. To my knowledge they never published real numbers on how much they found to be backdoored but I imagine that it is a LOT worse than any of us would guess.
This is what firewalls are for, but no consumer uses them.
Kind of a big fucking problem when your damn firewall is backdoored man.
Do you know what CISCO does?