Chinese state hackers spent years breaking into 9 US carriers and recording presidential campaign phone calls. T-Mobile stopped them with a pair of scissors. Four security staffers drove to a data center in Bellevue, found the compromised box, and physically cut its cable. The scissors were the technically correct move. Salt Typhoon lived inside the lawful-intercept systems, the wiretap infrastructure every carrier is legally required to run. When attackers control the layer that watches your…