The Null Device

2012/1/30

According to this story a British visitor to the US was arrested and deported after he posted to his Twitter feed that he was planning to "destroy America" and "dig up Marilyn Monroe", immediately flagging him as a terrorist threat.

The Department of Homeland Security flagged him as a potential threat when he posted an excited tweet to his pals about his forthcoming trip to Hollywood which read: 'Free this week, for quick gossip/prep before I go and destroy America'.

If the story is true (and, given that it comes from the Daily Mail, which never lets the facts get in the way of marshalling popular outrage, that is a considerable 'if'), it implies two things:

  1. The US border control agency (not the CIA or NSA or some other super-elite agency that hunts threats through the shadows, but the guys who scan passports) has a feed of intelligence gathered from the public Twitter feeds of anyone seeking to enter the US (and possibly other social media connected to their identities). This has a number of implications: where does the data come from? Is it just what is publicly linked to the poster's profile online, or does it come from clandestine sources (i.e., a list of user-generated content sites posted to from the visitor's home internet connection, as hoovered up by ECHELON)? Is there some NSA supercomputer quietly building up profiles on several billion internet users, with parts of these being sent to border security if some other part of the surveillance apparatus detects a keyphrase (say, the words "destroy America") in a feed linked to a particular individual?
  2. Given the nature of the tweet (which any reasonable person, had they overheard it in a pub, would conclude was a joke), it implies that, as far as the US Department of Homeland Security is concerned, the entire internet is an airport security zone, where joking about, say, carrying bombs or even an absurdity such as destroying America (how exactly would one go about accomplishing this?) is a punishable offence. There is a reason why joking about bombs at airport security screening lines is prohibited; namely that constraining the allowed range of behaviours whilst passing through a security checkpoint allows the checkpoint to operate. This rationale doesn't extend to applying the same rules to any idle banter uttered by a traveller within earshot of electronic intelligence gathering apparatus, and immediately punishing wisecracks.

If this system is as imperfect and prone to false positives as, say, the No-Fly List implemented in the US after 9/11, where people were banned from flying because their names and birthdates were close to those of suspected terrorists or other troublemakers, you can imagine the zany hijinks that might ensue the next time, say, that a business traveller shares a name with a Trotskyist agitator or radical cleric, or just some joker with, shall we say, different standards of self-restraint.

From what I gather, it is very difficult if not impossible for foreign visitors to seek legal redress against the US immigration authorities. More's the pity, as that will allow such absurdities to stand; with no chance of censure, the Homeland Security officials who made the call technically did the right thing, as there is nothing eligible for consideration to balance the (infinitesimally tiny) chance that they might have caught an actual terrorist. (In fact, they might have to deport enough people to exceed airline capacity out of the US and the capacity of airport holding cells for it to register as a problem.) Anyway, it seems that the moral of this story is: if there's any chance of your wanting or needing to visit the United States, don't joke about bombs or terrorism or drugs or non-specific acts of destruction, or indeed anything other that you wouldn't talk about in an airport security queue.

(via Schneier) paranoia stupidity the long siege twitter usa 4