The clearest statement I’ve seen, which puts in a nutshell my own thinking, is in the final paragraph of a letter to the editor in The New York Times of last Thursday (from Eugene Cosloy in Maine):
“Safety and security are not our birthright. They were never guaranteed in the Constitution, unlike our liberties.” (Cosloy’s letter concludes “. . .which too many of us are willing to barter away.”)
The constitutionally guaranteed liberty most germane to government internet and phone surveillance is found in the Fourth Amendment:
The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.
The question of whether or not internet and phone surveillance programs violate the Fourth Amendment ultimately must be decided by The Supreme Court.