Discussions of threat mitigation are irrelevant so long as the threats and their countermeasures remain undisclosed. There can be no productive debate when one side knows everything and tells the other side nothing.

It doesn't matter if surveillance is used only for good (evidence suggests otherwise, though); if the surveillance organizations have all the power to operate in secrecy and distort the truth when questioned by the legislature, their "trust us" assurances are wholly untrustworthy.