Historians of the Constitutional Era of the United States (1789-2001, RIP) will recall the Fourth Amendment to the Constitution, the one that used to protect Americans against unreasonable and unwarranted searches.
The Supreme Court had generally held that searches required a warrant. That warrant could be issued only after law enforcement showed they had “probable cause.” That in turn had been defined by the Court to require a high standard of proof, “a fair probability that contraband or evidence of a crime will be found in a particular place.”
The basic idea for more or less over 200 years: unless the government has a good, legal reason to look into your business, it couldn’t. As communications changed, the Fourth evolved to assert extend those same rights of privacy to phone calls, emails and texts, the same rules applying there as to physical searches.
That was Then
It was a good run. The Bill of Rights was designed to protect the people from their government. If the First Amendment’s right to speak out publicly was the people’s wall of security, then the Fourth Amendment’s right to privacy was its buttress. It was once thought that the government should neither be able to stop citizens from speaking nor peer into their lives. Folks, as our president now refers to us, should not have to fear the Knock on the Door in either their homes or The Homeland writ large.
In Post-Constitutional America (2001-Present), the government has taken a bloody box cutter to the original copy of the Constitution and thrown the Fourth Amendment in the garbage. The NSA revelations of Edward Snowden are, in that sense, not just a shock to the conscience but to the concept of privacy itself: Our government spies on us. All of us. Without suspicion. Without warrants. Without probable cause. Without restraint.