> This seems like a poor reason to ban an application/website/whatever. Reminds me of elementary school drama. Find a legitimate and/or legal reason (e.g. the mass harvesting of biometric data, unbeknownst to the users, being fed into some opaque government-ran database) or it should not be banned.

Um, no. Reciprocity is a pretty key concept in international relations, and a legitimate reason to take retaliatory measures. Also "we would rather not grant our adversary this advantage" is another legitimate reason to take action.