what makes government spying legitimate?

There are many tests one could use to judge public policy: Does it work? Is it cost-effective? Are the side effects acceptable? Is it consistent with our political and moral values?

One of the most important tests to use on the newly reported electronic surveillance programs is, is the activity legitimate? If not, then it should be abandoned. If it is, then other tests can be applied.

For me, policy legitimacy requires adherence to the Constitution and to a fair formal process. From what I've learned so far, the NSA programs meet that test. They are based on, and restricted by,  laws passed by the Congress, not merely an assertion of presidential prerogatives in response to alleged dangers. They are subject to some kind of review -- also called oversight -- by the judicial and legislative branches of government. Unlike the warrantless wiretapping during the Bush administration, the NSA programs require approval by the FISA court. Unlike many other secret programs, they have been briefed to the congressional intelligence committees. And unlike many of the worst-case depictions of what theoretically could happen using the new technologies, they are targeted on foreigners and actions abroad, not on Americans here at home. NSA people have a strong culture against domestic activities.

These judgments do not mean that the process is perfect. Obviously the oversight could be more rigorous, as could the vetting of personnel given the clearances to participate. Maybe we have gone too far in outsourcing intelligence activities to contractors rather than sworn officials. [About 28% of the people working in the intelligence community are contract employees.] Maybe we have gone too far in stressing the "need to share" information to thwart terrorists and need to move back toward the "need to know" standard.

But for what it's worth, I'm more outraged by what the Government can't collect and keep regarding gun purchases than by what it can do through NSA surveillance.