Benjamin Wittes wrote:

If you were shocked when you read the first paragraph of this post and relieved when you read that the agency doing all this collection is not NSA but the good guys over at the Library of Congress, and that the good guys are actually planning to make that data available widely, why did you have those reactions? And do those reactions make sense?

You asked, so I'll answer. I didn't have those reactions, and there are a couple of important observations to make about why.

First, I am cognizant of the public nature of public social media. I choose what to post on twitter and what not to post on twitter. I know that what I post to twitter can be read by anyone and that is my intent. What I post on Facebook is slightly more private than what I post on Twitter, and I am cognizant of that distinction. What I type into a search engine is much more private and may be more personal.

Advocates of mass surveillance often pretend that these distinctions are irrelevant. Because I post things about my personal life on Twitter and Facebook, they argue that it is therefore irrational for me to be concerned about surveillance of my search queries or call records. This is a weak attempt to rationalize away legitimate privacy interests.

Second, the idea of the NSA monitoring twitter may raise a concern that the agency is targeting people for investigation on the basis of their speech, which can deter people from expressing disfavored opinions. However, this concerned isn't raised simply because the NSA collects the data. The NSA would be remiss if it ignored the public postings of various terrorist organizations and their compatriots. I think the real question is what kinds of statements by someone can create a reasonable basis for a deeper investigation which opens private things.

Third, I don't think that the LOC should archive deleted tweets. Doing so undermines the decision by the poster to remove that content, and content gets removed for a lot of very good reasons, particularly in a medium where it is easy to write brief things that may be misconstrued when viewed from another perspective. However, it wouldn't bother me if the NSA monitored deleted tweets. Its not a privacy issue, its a matter of respecting people's ability to withdraw misstatements.

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