In a proper, functioning democracy it is assumed that we all obey the law. We are all presumed to be innocent, not just "until proven guilty" of an offence, but – more mundanely – in everything that we do. In the absence of supporting evidence, the authorities are not permitted to regard anyone with suspicion.
This is why the police must get warrants to spy on someone.
All of this is logical, of course: in a democracy, the police ultimately work for the people. For example, through the democratic process, the people can decide to disband the police.
Right now, it doesn't work that way. Many "western" governments view everyone with suspicion. They collect and share, in bulk, data on all our internet activities (the 5 eyes group, the Nine Eyes and 14 Eyes alliances). They say that access to these data is controlled by laws that respect our freedoms. But this is not valid – the mere collection of the data, to be accessed at some point in the future, is a gross invasion in and of itself. Also, it's worth noting that the laws and controls in place don't sufficiently prevent inappropriate access to these data (of, overwhelmingly, innocent people going about innocent activities!).
It turns out, though, that they're finding it hard to break strong encryption.