When the Internet was in its infancy, George H Bush, former director of the CIA was President.
He / his administration created the framework of rules that essentially killed any semblance of privacy.
They argued and saw the Internet as being in the public sphere (I am positive that’s not how they saw their own digital communicatios, people making decisions like this are almost always hypocritical, no different than a ballpark. Anything over IP as far as the government is concerned, free game.
Realize you need a search warrant for a car, home or even to open and read a letter. But the rules with anything digital are entirely different.
Also... Over time you began having smart phones, cars that are networked, smart home meters, smart watches, smart appliances, cameras on every street intersection, all your medical records became digital, so did a request for a prescription, your library, etc. But everything over IP is still “free game” as far as the Intel Community sees it.