Ask HN: Should more countries block Facebook and Google?

In light of the recent Cambridge Analytica scandal, it is now obvious that Facebook and Google have an outsized influence on billions of people's thoughts.

This can manifest itself in changing the outcome of elections, attitudes towards religion, social issues, privacy, war, etc.

From a national security standpoint, it seems reasonable for most countries to ban these services. In China, this move was critical for their government. Thoughts?