[II2II]

Protecting children, fighting terrorism, and other hot button rationalizations are definitely true. Those who try to discount those lines are either ignoring real problems or are as guilty of having ulterior motives as those they accuse. That said, there is certainly plenty of reason to question the consequences of violating people's privacy, and likely plenty of reason to question its effectiveness. For example: having all of the evidence in the world is going to do very little if it is buried to protect an individual or an organization.

As for plausible excuses to violate people's privacy ... I am not so sure about that one. It certainly may be true when you look at things at an institutional level. It may also be the cases that everything looks like a nail when you have a hammer, which is to say these organizations may be looking at evidence gathering as an exercise in data harvesting since information technology is currently the most popular tool at hand. While I don't think there is a clear-cut answer at an institutional level, I do believe that having the data at hand opens up many avenues for abuse. Institutions lobbying to collect that data may not have the intent to abuse it, yet individual members of the institution may find excuses to violate people's privacy since the data is at hand.