Why cut cables - slow, tedious, not very effective given how many there are - when you can mount attacks like the accidentally-discovered XZ Utils malware that could easily have shut down the entire Internet? The supposed source, one "Jia Tan" seems to have been a Kremlin-sponsored Russian hacker group that executed a very careful, well-planned, and discrete hack of Linux. As Linux is the OS for nearly every web server and DNS server out there, it's clear that using open-source OS has now become a non-viable option. It will take a few years, however, to implement more secure approaches and until then the Internet remains wide open to similar attacks - indeed, many pieces of malware may already be in place undetected.