Assuming that you agree that the government should not have the right to install mandatory CCTV cameras in private residences, where do you draw the line betwee

Assuming that you agree that the government should not have the right to install mandatory CCTV cameras in private residences, where do you draw the line between that and eavesdropping on people's digital communications? What is it about digital communications that makes it reasonable for the government to listen in? I don't see any difference between the government CCTV in your bedroom and the Whatsapp case, except that Whatsapp could be spied upon much more cheaply and efficiently (were it not encrypted).