Should Facebook, Twitter follow IM providers and block access to U.S. ‘enemies’?

Facebook and Twitter should join instant messaging (IM) services and block access to U.S.-sanctioned countries in order to avoid running afoul of the government’s trade embargoes, say legal experts.However, others say that doing so would be premature and run against the U.S. government’s goals regarding trade embargoes and for bringing democracy to the countries.
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