There is a democratic consensus that what the NSA is doing is wrong. The world on the whole certainly believes what the NSA is doing is unacceptable. It clearly violates article 12 of the UDHR, though of course we both know that not a single country on this planet really takes that document seriously. Even a majority of polled citizens of the USA believe that the unveiled programs are overreaching. Perhaps that's not broad enough for your taste, though if that is the case then I don't see how there's a broad belief that what the NSA is doing is right, either. Perhaps you can't stand the way pollsters have a habit of wording their questions with politically charged language; no disagreement there.

But even without democratic consensus there isn't a genuine distinction between the "second" and "third" ways you mention. Pedantic legal arguments are themselves built upon philosophical (transcendental, if you will) understandings of right and wrong; they cannot be detached from one another. That in courts we pretend otherwise is irrelevant. We make that distinction without a difference at our own peril. The spirit of the fourth amendment cannot be found strictly "in the light of the text and in light of the history." The raw text and history describe how the laws came into play, not why they did. To say that the fourth amendment was created because the founders didn't want anyone to have the ability to abuse Writs of Assistance to rummage through your house and home, completely ignores the underlying philosophical objection to such actions. I believe it's clear from the writings of the founders that, in penning the constitution and its initial batch of amendments, they weren't merely objecting to specific instances of wrong doing nor the technical implementation of such malice; they were, fundamentally, objecting to the very philosophy that suggested any person could possibly have a legitimate authority to rummage through the entirety of someone else's life at will and without any constraint or oversight. It wouldn't matter if they were rummaging through your house and home or your PO box or your safe deposit box or your Dropbox account. It is the philosophy that matters, and that the fourth amendment says nothing about computers or correspondence doesn't negate the philosophy that the founders were acting upon during their time.

In any case, I don't personally think that how the founders in the 1700s felt is somehow automatically relevant to the year 2013. We are living here now, not them. But for sake of argument, I suspect if I approached them with a system that permitted the "scanning" of all letters sent throughout the colonies without "actually reading" them until a "trigger" word was found; and that I pinky sweared that only trigger words relevant to national security would ever be utilized by this system; and that a secret court with sealed proceedings and opinions would look things over every couple months; they'd laugh in my face until they noticed I was dead serious, and then proceed to berate me for even suggesting something so tyrannical. To suggest that the founding fathers were appalled by the ability of a British official to abuse a Writ of Assistance to dig through their effects in their homes, but somehow wouldn't be appalled if the official decided to instead wait for the founders to place their belongings in a safe deposit box at a bank before seizing them, strains credulity.

Suffice it to say, I don't believe that either of the major legal systems on this planet today are really just. Common law, and the jurisprudence it confers, has a nasty habit of trying to apply the same rules to situations that are either entirely different or else similar in the most superficial of ways. In a zeal to ensure everyone receives equal treatment under the law, we've mistakenly decided that we will all equally suffer under precedent that is quite possibly not at all applicable outside of its initial case, rather than applying the spirit of the law to each and every situation as it arises. The capacity for a single shitty ruling to establish a precedent that must then migrate all the way to the supreme court to be overturned, is a colossal failure of the common law judicial system in my eyes. Civil law doesn't fair much better. It too wants to ignore the philosophical motivations of the statutes it upholds and is just as guilty of the same grievances. Though I do suspect that common law would fair better under reforms than civil law.