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summary

basic technical challenges
  + system reliablity
  + insufficient data
  + datasharing ineffective without prior record
  + preventative identification requires data 

misidentification trap

legal & political barriers

enormous technical challenges & fiscal costs
  + database systems holding so much information
  + for so many subjects
  + updated so regularly
  + 


A national identification system with centralized data collection will be ineffective in accurately determining terrorists and will impose heavy costs on society.  Due to the limits of technology and available information, any system for uncovering terrorists before they commit terrorist acts would produce a system that would reliably misidentify both terrorists and innocents.  Further, existing constitutional protections may pose challenges, while political acceptance of such a system may not be as clearcut as simple polling suggests.  Finally, the enormous technical challenges of centralized data collection, would lead to enormous financial costs without any guarantee of a useful system.

Any system capable of identifying a significant number of actual terrorists based on attainable data will inevitably label an enormous volume of innocent parties as terrorists.  Further, because there are certainly several orders of magnitude more innocent citizens than there are dangerous terrorists, it is nearly certain that any system with less than perfect reliability would identify more harmless people as terrorists than it would identify dangerous terrorists.  In addition to the terrorists it misses, the large number of identified innocents would form a nearly insurmountable barrier to finding the actually dangerous parties, nor would such a system reliably identify all terrorists.  Finally, the more actual terrorists such a system identified, the more innocent parties it would identify.  Thus, like car alarms, the most sensitive systems would rapidly get tuned out, because they would react to many circumstances that were not actually relevant.

There are institutional and political barriers to the construction of a centralized database.  The constitutional amendment preventing unreasonable search and seizure would be used as a basis for many legal challenges.  Additionally, support for a National ID system has waned considerably since september 11th.  While it is still ....  Historically within the united states, and across various nations, many proposals for national id systems have been proposed and rejected.  

Such proposals have largely been advocated by the companies that would be supplying the technology, and law enforcement agencies which advocated them as a solution to many other problems before september 11th.  There is a great risk that such information would be used in ways that would be subject to institutional mission creep, so that regardless of official restrictions, in practical application, many institutions would start to use the information inappropriately or illegally.

The technical challenges to such an endeavor may be surmountable, but would certainly be very expensive.  Maintaining a large scale database, updated on a regular basis with frequent access ...


abuse of the system
identification mistakes
privacy issues